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  1. VKN - and anyone else who may benefit/care: I’m going to attempt to smooth your ruffled feathers. I DO want very much for you - and everyone else - to succeed ‘beyond your wildest dreams’ (exceed expectations). If I didn’t, then I wouldn’t still be typing, or otherwise infecting APN with my demonic ‘attitude’ - or ‘putting up with’ hostile lying trolls. I hesitate to craft the definitive ‘definition’ of iAVs at this time, but I’ll ‘give a shot’ at listing what I consider to be the basic requirements: Water: fresh (non-saline), clear (non-turbid), non-polluted (no biological pathogens or ‘chemicals’, metals or nucleotides). Basically, potable water. Rain water is strongly advised for the vast majority of applications/locations. Its also free. (collect and store securely in advance of need). Sand: well-draining, no clay/slit, and chemically inert (does not raise or lower pH of water that comes into contact with it). We’ve been all over this topic in detail repeatedly. “Sand†is a specific range of particle size, not a specific material/mineral composition. Quartz (SiO2) is recommended if/where at all possible, but some other inert minerals and glasses may work well also. Others certainly will not. Operating beyond the scope of our recommendations is at the sole responsibility/risk of the operator(s). Furrows: on the sand surface to distribute ‘water/waste’ evenly across surface and also to keep aerial plant material dry. Pristine sand furrows are stabilized by bacterial films, detritus and/or alga. Attempt to maintain as much ridge area (mound between furrows) as wide as possible. Furrows include both between all rows of plants and around the entire perimeter. Flood/Drain: Saturate filter substrate and then allow it to drain completely once every 2 hours (approx.) during daylight. Leave drained overnight. In the tropics, first ‘cycle’ can begin somewhat pre-dawn and the last start at dusk (finish draining just after total darkness). Since drainage also occurs during the pumping interval, presuming sufficient drainage, one can pump 1/4 up to even one-half of a FT volume per cycle without reducing the FT volume by more than 10 to 15% at any given time. ‘Tank’ (fish containment), Its capacity, proportions, shape (especially bottom slope) and the pump type/location need combine (‘work together’) to effectively allow solids to settle, and collect in a region/zone that the pump will readily extract/remove when it comes on. Try to schedule irrigation volumes sufficient to exchange (turnover) the FT at least twice each day. More might be ‘better’ - which can be accomplished several ways (not described here to avoid confusion) but not recommended to do so by shortening the on cycle interval significantly. Fish/Feed: Sufficient fish biomass and feed input consumed to satisfy fish and generate sufficient ‘waste’ to fertilize the number and species of plants being grown - not feed/stocked more than the filter/microbes can process continuously. This will vary by fish species, age (size), density, DO, pH, Temp, of water, and feed composition/conversion. Do not feed in the evening (allow for complete tank volume exchange between the last feeding of each day and dark). Sustainable fish load and feed rate also varies somewhat depending on type of plant species grown (e.g. leaf vs fruiting) and somewhat on the stage of development/maturity. Too many fish eating too much feed and respiring too much TAN for the size of the biofilter bed in current use is not advised. One could get away with this in the short-term but not over the medium- or long-term. pH; iAVs is dominantly (90-95%) Horticulture - by mass and economic value in most markets). Maximal fish production is NOT a goal nor advised. Vascular plants strongly ‘prefer’ (grow best) in range of pH 5.5 to 6.8 (extremes) and optimally 6.4 +/- 0.4 (variance range depends n specific species). Believe it or not. If one is satisfied with the results of one’s efforts, then that’s wonderful, really!. If one wants to improve one’s circumstance further, then consider accepting best-intentioned advise. Soil microbial ecology. Microbes evolved along with the plants they sustain/interact with, meaning they too benefit from pH in the ‘optimal’ range. In a ‘controlled environment e.g. greenhouse Pests and diseases: Take every prevention precaution possible (too many to describe here). A common vector is humans: limit and pre-sanitize all visitors and workers. Monitor for any/all developing problems continuously and have appropriate remedy available immediately. A gram of prevention yields many kilos of cure. Use integrated pest management strategies extensively (employ beneficial insects, bacteria, and plants). Use insecticidal soaps (Potassium salts of fatty acids) and plant-based extracts with care (minimize/eliminate contact with filter substrate) Maintain air temperatures and humidity levels appropriate to the plant species being grown. Shade, fogging, evaporative cooling can each be effective for cooling, either individually or in various combinations. Always provide ample ventilation and continuous air movement within a greenhouse. Above May Not be stated the best way possible: Its just what keystrokes I activated this morning. Any remaining gaps, errors or omissions are not intentional and regrettable.(and correctable). Questions to ask yourself - OR better yet, to share your responses to here: Is your water ‘clean’ or is it contaminated? (e.g. nitrates, phosphates, pathogens, …) DO you have/use an inert, well-drained sand (sharp SiO2 preferred) DO you flood saturate and then leave drained on 2+/- cycle during the day? Are you maintaining ‘system’ (water) pH in the range preferred by plants for optimal growth? Above pH 7.0 is NOT recommended. Do you have a ‘balanced’ fish load and sustainable feed input rate? Are you growing nutrient demanding crops (solely lettuce is not advised)? If you answered Yes to ALL of the above questions, then congratulations … you’re amazing and quite unique. I say that in spite of the fact that I will always insist that AP is a disease. Some diseases are curable, others are not. You’re Welcome. ============ PS: Yes, I am fully aware that focusing on plant production (minimizing fish to plant ‘ratios’) is viewed as blasphemy by many, if not most, aqua-holics. This is not a concern I have. No one is attempting to prevent anyone from doing precisely whatever they feel like, be that rational or otherwise. Don’t freak out or invent fallacies. I am describing what iAVs was intended to do, aka how it ‘works best’ (to date). What anyone who is NOT literally doing/using iAVs “feels†about claims and goals thereof is irrelevant to me. Do it or don’t. Your choice. Your life. ....... BTW: Not seeing is not believing ... and vice-versa If you do undertake iAVs, then please accept our advice in the spirit intended. My/our intention is for you to realize the best outcome possible, with the greatest cost:benefit possible. There is and never has been anything (positive) ’in this’ for me. iAVs has always been exclusively about you (others). That is all. No fee, No exchange, No refund. No apology.
    9 points
  2. yahoo2

    Why Aquaponics?

    The potential as an educational tool is staggering. Concepts that normally take years to fully understand (or perhaps never) can be grasped in just weeks or months. Everything happens so fast in simple fish water. I watch you guys as you move on to wicking beds, poultry, hydroponics or whatever and I see sharper skills in nutrition, propagation, feeding, chemistry, finance, managing seasonal climate, improving yields, trouble-shooting and fine-tuning costs. I also wonder if there is a positive effect on our diet and health from a change in attitude, I've not completely thought that through yet!..... seem plausible.
    9 points
  3. In light of all the fantastic discussion around mineralization and the extensive acceptance of filtration in aquaponic systems and now the gradual realization the solids have a greater role to play in these integrated systems, below is an extension of The Evolution of Aquaponics article previously published. This is in line with this particular project flow design. The same "Outsida Normalous" described below is the next natural progression of evolution and can be simply applied to the small producer or backyard aquaponics. I hope it encourages more discussion around such a simple, yet very effective design.
    9 points
  4. mhaigh

    iAVs in Oklahoma

    iAVs in Oklahoma – #1 I thought I would give all who are interested a recap on my experience with my iAVs in my backyard. Like a good many of you, I have a full-time job, but I long to be out in the greenhouse most of the day/night! (note: this is the same post from the iAVs website, but thought it might get a bit more "play" here on AQN). Background I had operated a deep water culture (DWC) setup starting in 2011, but struggled to keep it productive between temperature swings, bugs and lack of time to attend to the system. When fall came, it was time to harvest the Tilapia and wait for next spring to get started again…..I really knew that I wanted/needed a greenhouse. I came upon a German engineer who had designed a greenhouse modeling the Chinese Solar Greenhouse lean-to model which incorporated a DWC system as a part of its energy mass. As good fortune would have it, I had an opportunity to visit Frankfurt in 2013 during the bi-annual ginormous trade show – ISH-Frankfurt. My boss and I spent a week exploring the advanced heating technologies that Europe has developed in their mechanical equipment (think Mecca for boiler junkies). I tracked down Franz via the web and we became email-friendly and he suggested that we spend the week in Heppenheim Germany and take the free train ride into Frankfurt each day to the ISH show – a good plan since hotel rooms in Frankfurt can be $1000+ USD a night during ISH week. In between daily trade show visits and nightly late drinks in historic Heppenheim’s cobblestone square, Franz would take us around to GHs he had built and show us the energy saving features that he was incorporating into his design. Very informative and really got the GH construction bug fully energized! Fast forward to late 2014, I was slowly building out my 24′ x 24′ GH attached to the south wall of my shop building…..following Franz’s general layout for the adapted Chinese design. My plan was to go DWC rafts again, but when I started following an Aquaponics forum thread discussing the merits of the design-operation of the iAVs. The greenhouse under construction. The completed greenhouse. Fortunately I had not gone too far down the track with the DWC and there was still time to take a fork in the road. I had chimed in a few times on the Aquaponics thread, but could see that there was way too much drama involved in the discussions. So, I tracked down Dr Mark McMurtry thru an old email address (thank you Google) and we started trading ideas. (correction: I would pose an idea and then I would realize that I need to shut up and take copious notes and try to follow the Jedi Master). Dr McMurtry was good enough to humor me and help me to see that maybe his 30+ years of iAVs experimentation might save me a lot of dead ends and restarts! The sand bed before I added the sand. Unfortunately, I had installed a full underground SHCS heating/cooling system in the floor of my GH which precluded me from setting the fish tank below grade. Instead I had to install a shallow sump to collect water that drains from the sand filter grow beds and then pump it back up into the fish tank which sits just inside my shop building (see photo for details). I say “unfortunately†but in actuality I am quite pleased with the performance of the heating system. Even with outside temps down as low as 15F, the air blowing thru tubes under the GH keeps the temp inside in the mid to upper 40’s……..all done with less than 200 watts of fan energy! When the sun comes out even on a 20F day, the greenhouse is floating in the mid-70’s within an hour or two. Our use of an underground heating and cooling system necessitated a sump tank. The sump tank with the cover in place. OK, enough background, now on to the star of the show….iAVs. Finding the proper sand was time consuming, I had gone to at least 4 different sand suppliers before I found a sand that was “in the ballparkâ€. After running a 5 gallon bucket perc (hydraulic conductivity) test as directed by Mark, we determined that the “bunker sand†(local supplier’s name for his coarse sand) was close enough to try. A few more smaller particles than ideal, but overall the profile was decent. A minimum percentage of clay/silt was a plus. So…..my observations regarding the iAVs setup after running for several months. Setting the fish tank below grade is best, the extra sump and pump(s) adds complexity to the system and another failure point to have to monitor and repair as needed. Not being able to have enough fish/feed load has greatly hampered the growth of the plants. I am still only feeding my (100) hybrid bluegills about 35 grams of food per day. Basically just a smidgen over an oz of food per day is all the fish are consuming. This is hampered by the low fish tank water temperature as I am not heating the water. When the water temp is over 60F the fish consume about twice as much food, under 55F they are not very interested. Due to high pH in my source water (Oklahoma City water comes out of the tap at 8.5 this time of year, even higher in the summer sometimes…and the Chloramine has to be neutralized too), the plants are not thriving. Now they are healthy and green and we have been eating some brandywine tomatoes, leaf lettuce, green beans, broccoli…..but the growth is slow. I am pretty certain this is due to the 7.4 pH. I am starting to try to lower the pH (patience is overrated sometimes), so hopefully I will see a big uptick in plant action after I get below 7.0. February 1st 2016 Update: I have been slowly dosing with 30 gallons of 6.0 pH water treated with Nitric acid every few days. Although I can barely see the pH trending down (it maybe 7.3 now) the plants have begun to respond. The greens, broccoli and lettuce are definitely perking up. I really think the high pH is due to a high alkalinity in my city water, I plan on getting it tested by a local aquarium supply store to confirm what the true issue with pH “lock†really is. Although I have been general pleased with the stability and growth in my iAVs system, I know that my pH, low water temp and low feed rate have really hampered the true capability of the iAVs system. I will try to update as conditions improve. Present conditions notwithstanding, I am pumped about iAVs. Simple and robust and inexpensive to operate. April 11, 2016 Update Plants and fish are doing well, BG are eating about 200 grams per day. I am still hampered by high carbonates which (thru my own stupidity) were not checked before I purchased the sand. I was so fixated on particle size (and trusted the sand supplier's "its just silica sand" comments) and didn't run the simple vinegar test to check for Oklahoma limestone (or equivalent carbonate) which is buffering the pH from dropping below 7.3. I have been waiting semi-patiently for the the nitrification process to start to bring the pH down naturally, but after 60+ days no movement. My next plan is to lower my makeup water pH down with acid. I have located a chemical supplier who will sell me a gallon of sulfuric acid, so I will begin dosing in the next few weeks......subject to day job "interruptions". My kH is running about 6-7 in the sump after water trickles thru the sand bed. Here's a video of what you don't want to see when you test the prospective sand.... Sand Carbonate Test (after the fact) Video.mov Mike
    8 points
  5. "Are you intending to inoculate your filters with nitrifying bacteria and/or other micro-organisms? If not, how do you intend to (so-called) 'cycle' your system(s)?" "We intend to keep it very simple. Add the first batch of young fingerlings between 5 to 10 g in weight in the large body of two culture tanks. Add a small batch of plants in small segments of the respective two modules of sand beds. We have divided the total number of sand beds into 6 such modules. Feed the fish at a reduced rate which will be gradually increased in direct proportion to plant growth and the water quality factors. Once things are normalized, incrementally increase the plant population based on the feed input. Dr. McMurtry, what else should we take care?" I found that by inoculating with a suspension of Nitrosomonas and Nitrobacter one can 'jump-start' a 'system' in days instead of 2 to 3 weeks. One such product available in the US is Fritz-Zyme #7. I used this product in the ratio studies at approx. 1/2 the recommended concentration and had near immediate results. One may be able to apply 1/4 strength and shorten the 'cycle' time to a matter of a couple days. Obviously, a source of ammonia needs be relatively immediately available to the bacteria for them to survive and multiply. I have no idea as to what similar products may be available in India. http://www.fritzzyme.com/index.php?p=fritzzyme-nitrifying-bacteria If you have access to a source of active, well-developed organic compost, you could also sprinkle a small handful of that into the furrows nearest the water inlet end (the water will distribute the microbes through out bed volume). This would likely inoculate the media with at least some of your indigenous strains of amoeba, mycorrhiza, nematodes, protozoa, etc. and accelerate development of the soil microflora. I actually never did this myself (so isn't actually necessary) but I would anticipate that this too would 'jump-start' populating the sand with beneficial organisms. Another possible source of inoculant is small amounts of a VERY humus-rich soil. Don't use much, a little bit ( e.g., a couple tablespoons per furrow) is enough to get things started in the right direction. WRT "what else" - successful growers (any/all) pay close attention to the details, details, details ... As Ludwig Mies van der Rohe is infamous for stating " God is in the details." (albeit I'm quick to add that, personally speaking, that 'God' (however imagined) is a 'detail' that I actively reject). Nevertheless, do become an active, astute observer of everything going on in the environment and particularly how the plants are responding in every nuance. Train your operators to be careful/informed observers and record developments as they occur. Skilled gardeners/growers have developed a 'sixth-sense' based in their careful observations and come to a heightened sensitivity as to the needs/responses of their crops. Yes, this takes time (experience) but one has to start somewhere, so I suggest immediately if not sooner. On the topic of what else, If you provide an ideal environment for any crop or species, one has simultaneously created the ideal circumstances for the diseases and pests thereof. Therefore, do take every possible precaution (no matter how mundane and seemingly insignificant/trivial) to prevent pests (eliminate vectors). I would be remiss if I didn't also point out that people (and their clothing) is generally how most pests and diseases enter a properly screened GH. I council that in a commercial context, ONLY authorized (required, trained) operators are allowed entry and even then following adherence to proper sanitation measures/precautions - EVERY single time for everyone. Same goes for tools and equipment brought in - for metals and plastics a dip/spray with a solution of Copper Sulfate is typical in GH sanitation protocol. In the event that you want visitors (for any reason), that you require them to at minimum decontaminate their footwear (&/or wear cover slips), wash their hands with anti-bacterial soap and even provide them coveralls to cover their 'street' clothing. This may sound extreme precaution to some/many but I assure you that it is not. The vast majority of GH operations that fail is largely due to some pest(s) or disease infestation brought in by a worker or by the public (invited quests). A commercial GH operation is a business - period - and not a 'show & tell' (advertisement/promotional venue) or a stage-play for the public's amusement or edification. A commercial GH is not 'exactly' a medical operating theater or a micro-chip manufacturing facility but the closer that one can approach this level of strict sanitation the less likely it will be that a game-changing infestation will occur. 99% of effective disease/pest management is prevention. The other 1% is careful observation such as to detect the very first signs of a problem and to be prepared (in advance) to respond immediately (keep the problem from becoming a catastrophe). Some (random) info about CuSO4 http://npic.orst.edu/factsheets/cuso4gen.html - do keep this - and all similar compounds- far away from the sand beds and water - do not use as a pesticide either. Use only to 'treat' (wash/rinse) tools and equipment brought into the facility and allow to dry and/or rinse thoroughly before contact with the water, plants or sand. Many commercial growers will treat (sanitize) the tools used by employees at the start of every work day and/or when moving from one room or crop to another. Yes, growers go to extreme lengths to protect their investment and income streams. Those that do not adhere to rigorous sanitation protocol will fail - often sooner rather than later. Sanitation is paramount in a GH and the larger one's investment/operation is the more it 'just makes sense' to be obsessive to the point of a compulsive fetish. I can't stress this enough - but I tried. The following will 'sound like' blasphemy to mosts AP-ists. but personally I don't care how fast the fish are growing - so long as they aren't sick/suffering, ntm dying. What I care about is the 'waste' (nutrient) output. If the plants are receiving adequate nutrients, then the feed rate and soil biology is also adequate/appropriate. If the microbial activity and plant growth is vigorous, the fish will be/do just fine. Focus on the plant performance as a gauge of the overall system performance. Yes, the water pH, DO, temp needs to be appropriate to the spp. and monitored regularly, and the feed composition sufficient in all essential elements, but beyond that, let the plants 'speak to you' about how things are 'going' (growing). IMO, iAVs is 'about' horticulture (with fish 'wastes') and not 'about' aquaculture with tertiary water quality maintenance provided by plants. If the plants are doing fine, then the fish will be fine too. In most markets, the vegetables represent 90% or more of the potential revenue stream. If what one is 'after' is fish production per unit volume/time, then consider recirculatory aquaculture instead. Thus endeth this highly abbreviated diatribe.
    8 points
  6. Guys, I'm not sure how this discussion got so sidetracked on feed conversion rates, but if we're going to discuss them, then let's actually use the data. If you look at table 4 of the "94 HortTech Tables v.2.3" document, you'll notice a couple very important things: 1. The initial mean individual stocking weights (PMi) are vastly different in each of the three experiments, increasing with each subsequent experiment. 2. The initial stocking densities (Bi) are vastly different in each of the three experiments, increasing with each subsequent experiment. Now, look at the FCR's for each experiment: - FCR's get progressively worse with each subsequent experiment. See a correlation? See a pattern? FCR tends to get worse as fish age and grow larger. Growth rates also tend to decline as the fish age and grow larger. Both FCR and growth rates tend to be negatively impacted by increasing biomass density (stocking density). This is all common aquaculture knowledge, but worth mentioning nonetheless. Now, go back to table 4 of the "94 HortTech Tables v.2.3" document and compare those numbers to table 7 in the "J. WAS 94 Tables" document, which is a table of comparative data from other RAS trials that incorporated olericulture (growing plants). Compared to the other integrated RAS (integrated aquaculture/aquaponics) trials, you can make the following basic assumptions about Dr. McMurtry's FCR results: - In EXP 1, you see pretty favorable FCR's for the 1980's. - In EXP 2, they are about average, "par for the course", for that time period. - In EXP 3, they are pretty lousy, even for that time period. BUT... That's not really the whole story, is it? While the FCR's are interesting and definitely reinforce the bolded statements above, they are not a reflection of true FCR over the complete lifecycle (juvenile to harvest size) of the fish, as you would experience in most real world grow out situations. Each experiment is actually a snapshot of FCR's from different periods in the lifecycle (age/size) of the fish he used over the course of 362 days, and to complicate matters a bit more, in completely different stocking densities. Logically, you are going to have poorer FCR and reduced growth rates in larger fish, which are also stocked in significantly higher initial densities. That's what we have here, and I think it's safe to assume Dr. McMurtry was, himself, well aware of this, but he was working with the fish he had available. There's more though. With the Mozambique x Nile hybrids that were used by Dr. McMurtry, I would expect poorer FCR compared to pure Blues or Niles, so you really should only use the FCR's of "O. hybrids" in table 7 of the "J. WAS 94 Tables" document, and omit those of Blues and Niles. In my own experience working with and trialing numerous tilapia strains/species for many years now, pure Mozambiques, and hybrids based on them, tend to have inferior FCR to most Nile and Blue based strains, and growth rates really decline badly with Mozambique strains as they age (they tend to begin to plateau not long after reaching reproductive maturity, which they reach very early in life), which also contributes somewhat to the declining FCR's in Dr. McMurtry's subsequent experiments. Niles and Blues are more robust fish in general, and also tend to reach reproductive maturity much later than Mozambiques. They also don't suffer as badly from the "growth plateau" once they hit reproductive maturity. It's like comparing apples to oranges when attempting to compare FCR's of Blues and Niles to Mozambiques and Mozy hybrids. Yet, most FCR data available for tilapia is based on, you guessed it, Niles and Blues. Since we have some "O. hybrid" FCR data in table 7 from other comparative trials, and they're the most appropriate (apples to apples) let's use that for our... comparisons: - 1. O. hybrid all males (68g initial weight, 425g harvest weight) = 2.11 FCR - 2. O. hybrid all males (50g initial weight, 261g harvest weight) = 1.90 FCR - 3. O. hybrid all males (15g initial weight, 217g harvest weight) = 2.14 FCR Now, compare those to Dr. McMurtry's (weights rounded to nearest gram): - EXP 1, 1:2.25 (15g initial weight, 217g harvest weight) = 1.27 FCR - EXP 2, 1:2.25 (161g initial weight, 452g harvest weight)= 2.03 FCR - EXP 3, 1:2.25 (438g initial weight, 689g harvest weight)= 2.87 FCR So... looking at comparative #3 and McMurtry EXP 1, you'll notice they had identical initial stocking weight and harvest weight in common (after rounding), yet McMurtry's FCR was significantly better. Solid McMurtry win. The next closest matches would be #1 and EXP 2 (initial stocking weights are quite different but harvest weights are fairly close). McMurtry just barely squeeks out a win on FCR, but McMurtry stocked much larger fish, which would be to his disadvantage in this comparison. That ends up being a solid win for McMurtry because of that. There is no comparative data to put EXP 3 up against, since all comparison examples started with much smaller fish and also harvested much smaller fish. EXP 3, for all practical purposes, is not a good source for comparison on FCR anyway. We're talking about stocking a roughly 1 pound tilapia and harvesting it at roughly 1.5 pounds. Pretty unusual for a real world grower to START with a 1 pound tilapia. That's nearly a typical harvest weight already! I'd also expect inferior FCR's in tilapia that were available in the 1980's, as they had not benefited from the subsequent 25-30 odd years of genetic improvement through focused selective breeding programs that we have today. Fish nutrition has improved a great deal in the last 25-30 years too, so it would be expected that today's commercial pellet diets tend to offer better FCR potentials than those used by Dr. McMurtry back in the 80's. Perhaps another notable point is that the system pH was allowed to go down as low as 5.5 before being raised using calcium oxide, and was raised somewhere "above 6.0" with the calcium oxide application. Better FCR's would have probably occurred in more stable pH conditions, in the 6.8-7.2 range, which is generally believed to be more favorable to tilapia growth and FCR (but getting on the high side for the plants). Also, the fish were handled and sedated frequently for gathering biomass data. It was a trial after all, so was necessary, but this extra handling/stress likely caused a negative impact on growth rates and FCR as well, even if only slightly. All things considered, I think the FCR's that Dr. McMurtry achieved in his experiments are pretty good, considering when they were done, the parameters involved and the kind of tilapia that were used.
    8 points
  7. If you want to be successful with your aquaponics system, you will need to understand how the nitrogen cycle works. I will explain what the nitrogen cycle is, why it's important, how it progresses and how to ensure it works efficiently in your established system. Armed with this important information, you'll be well on your way to growing fish and plants just like the pros do. What is the Nitrogen Cycle? The nitrogen cycle is what powers aquaponics. There are several key players in the overall nitrogen cycle, but the ones who tie it all together are nitrifying bacteria. If these nitrifying bacteria are present in sufficient numbers to efficiently process toxic ammonia and nitrite into relatively benign nitrate, we consider the system to be "cycled". However, this doesn't simply happen overnight. It takes some time for the bacterial population to establish, usually between several weeks and several months, depending on various factors. When a system is just embarking on this process, and until it has completed, we say the system is "cycling". The words "cycling" and "cycled" are really just words used to describe the state a system is in, with regard to the overall process of nitrification. The Cycling Process Begins For all practical purposes, the nitrogen cycle starts when fish food (rich in nitrogen), or some other nitrogen source (like ammonia), is first added to the system. Fish food is the primary source of nitrogen input in an aquaponic system. Fish consume the fish food, utilizing about 25% of the nitrogen in the food for growth, and then excrete the rest as ammonia. This ammonia takes on two different forms in water, un-ionized ammonia (NH3) and ionized ammonia, called ammonium (NH4+). As previously mentioned, ammonia (NH3) is highly toxic to fish, but ammonium (NH4+) is not. Typically, only about 1-3% of the total ammonia nitrogen (TAN) in a system consists of this toxic ammonia form, but it doesn't take much to kill fish, so it has to be dealt with quickly. The system's pH plays a significant role in determining the ratio of ammonia to ammonium. Temperature plays a role as well, but to a much lesser extent. Without getting too terribly technical, the higher the pH and temperature, the higher the percentage of toxic ammonia you'll have as part of the overall TAN mix. The Nitrification Process Once there is sufficient ammonia in the system, the first group of nitrifying bacteria (primarily Nitrosomonas and some others) begin converting it by way of oxidation into nitrite (chemical compound NO2-), and the population increases rapidly as a result. We call this group of bacteria "ammonia oxidizing bacteria" (AOB). During this phase of the cycling process, the system will typically experience a considerable spike in nitrite levels and a reduction in TAN (ammonia/ammonium). However, just like ammonia, nitrite is also quite toxic to fish, so we rely on another group of bacteria to continue the cycle. Now that nitrite is present, a new group of bacteria (primarily Nitrobacter and some others) begin to populate the system. They convert the nitrite by way of oxidation into nitrate (chemical compound NO3-). We call this group of bacteria "nitrite oxidizing bacteria" (NOB). Nitrogen Uptake by Plants The vast majority of terrestrial (land dwelling) plants prefer their nitrogen (N) source to be in the nitrate form. Secondarily, they'll also take up ammonium, but in the presence of readily available nitrates, they'll take up ammonium in much lower amounts. Many aquatic (water dwelling) plants on the other hand tend to have a higher preference for ammonium over nitrate. These differences of N uptake preference between terrestrial and aquatic plants has frequently caused confusion for those just entering the world of aquaponics. Since aquaponics is primarily focused on terrestrial plant production, we're going to keep it simple and restrict this discussion to terrestrial plants and nitrates. Think of nitrates as "plant food". As long as you continue to add fish food, and the nitrification process is not hindered or interrupted, your system will continue to produce nitrates. These nitrates will then be "consumed" by your plants. If there are not enough plants growing in the system, nitrate levels will climb higher and higher. If you have an overabundance of plants in relation to the amount of fish food you are adding, the nitrate levels will fall, and your plants will compete for them immediately as the become available. Plant growth will then suffer. Maintaining the Nitrogen Balance There is no such thing as a self-balanced aquaponics system. Maintaining a healthy, productive aquaponics system requires some monitoring, and making adjustments when necessary. We strongly recommend routinely checking your system's water temperature, pH, ammonia, nitrite and nitrate levels. There are numerous electronic meters available for this, but they tend to be quite expensive, and are really only suitable for very large systems due to the high cost. There are also chemical test kits available, which are extremely affordable and provide very accurate results for our needs. We routinely recommend the API Freshwater Master Test Kit. It costs around $25 or less in the US, will last for about 800 total tests, and is available at many pet stores, garden pond stores and online suppliers. Armed with a test kit, you will be able to determine what adjustments you need to make and when you need to make them. Here are the most common scenarios you will encounter that require adjustments: Declining pH - Generally speaking, you will want to maintain your cycled system pH around 6.8-7.2. If it falls below this range, the nitrifying bacteria will be adversely impacted. You need to add a base. There are commercially available products for this, but you can also use relatively common chemical salts like sodium bicarbonate, calcium bicarbonate, potassium bicarbonate, calcium hydroxide, calcium chloride and many others. Specific recommendations are beyond the scope of this article, but will be featured in a later article related to maintaining pH levels. Rising ammonia levels in an established system - In a properly performing aquaponics system, ammonia levels should barely be traceable. The AOB's should be "processing" them almost as quickly as they become available in the system. There are numerous causes of elevated ammonia levels, but here are several of the most common: Overfeeding, inadequate biofiltration, interruption to the AOB population. Rising nitrite levels in an established system - In a properly performing aquaponics system, just like ammonia levels, nitrite levels should barely be traceable. The NOB's should be "processing" them almost as quickly as they become available in the system. Some of the more common causes include: Inadequate biofiltration, interruption to the NOB population or nitrate to nitrite "reversion" or denitrification caused by Anoxic/anaerobic (low/no oxygen) areas in the system where heterotrophic bacteria "convert" existing nitrates and accumulated solids into nitrite which the NOB's are unable to keep up with. Extremely elevated nitrate levels in an established system - It is usually ideal to have some stockpiled nitrate exist in the system, but if it begins to climb to extremely elevated levels, you could potentially risk a resulting nitrite spike due to denitrification. Either you need to decrease your fish food input, or even better, add additional plants to take up the excess production. Inadaquate or trace levels of nitrate in an established system - Either you need to increase your fish food input or reduce your plant mass by culling or harvesting. Final Recap As you can see, the nitrogen cycle is what aquaponics is really all about. As long as you take the steps to ensure proper nitrification is taking place in your system, you are well on your way to enjoying a productive system that provides you with healthy, homegrown food. As always, I invite any questions, comments or suggestions. Thanks!
    7 points
  8. Ravnis

    FAQ - What is IAVS

    A very good post of what is IAVS was submitted recently by Dr. McMurtry. I felt it deserved it's own thread. VKN - and anyone else who may benefit/care: I’m going to attempt to smooth your ruffled feathers. I DO want very much for you - and everyone else - to succeed ‘beyond your wildest dreams’ (exceed expectations). If I didn’t, then I wouldn’t still be typing, or otherwise infecting APN with my demonic ‘attitude’ - or ‘putting up with’ hostile lying trolls. I hesitate to craft the definitive ‘definition’ of iAVs at this time, but I’ll ‘give a shot’ at listing what I consider to be the basic requirements: Water: fresh (non-saline), clear (non-turbid), non-polluted (no biological pathogens or ‘chemicals’, metals or nucleotides). Basically, potable water. Rain water is strongly advised for the vast majority of applications/locations. Its also free. (collect and store securely in advance of need). Sand: well-draining, no clay/slit, and chemically inert (does not raise or lower pH of water that comes into contact with it). We’ve been all over this topic in detail repeatedly. “Sand†is a specific range of particle size, not a specific material/mineral composition. Quartz (SiO2) is recommended if/where at all possible, but some other inert minerals and glasses may work well also. Others certainly will not. Operating beyond the scope of our recommendations is at the sole responsibility/risk of the operator(s). Furrows: on the sand surface to distribute ‘water/waste’ evenly across surface and also to keep aerial plant material dry. Pristine sand furrows are stabilized by bacterial films, detritus and/or alga. Attempt to maintain as much ridge area (mound between furrows) as wide as possible. Furrows include both between all rows of plants and around the entire perimeter. Flood/Drain: Saturate filter substrate and then allow it to drain completely once every 2 hours (approx.) during daylight. Leave drained overnight. In the tropics, first ‘cycle’ can begin somewhat pre-dawn and the last start at dusk (finish draining just after total darkness). Since drainage also occurs during the pumping interval, presuming sufficient drainage, one can pump 1/4 up to even one-half of a FT volume per cycle without reducing the FT volume by more than 10 to 15% at any given time. ‘Tank’ (fish containment), Its capacity, proportions, shape (especially bottom slope) and the pump type/location need combine (‘work together’) to effectively allow solids to settle, and collect in a region/zone that the pump will readily extract/remove when it comes on. Try to schedule irrigation volumes sufficient to exchange (turnover) the FT at least twice each day. More might be ‘better’ - which can be accomplished several ways (not described here to avoid confusion) but not recommended to do so by shortening the on cycle interval significantly. Fish/Feed: Sufficient fish biomass and feed input consumed to satisfy fish and generate sufficient ‘waste’ to fertilize the number and species of plants being grown - not feed/stocked more than the filter/microbes can process continuously. This will vary by fish species, age (size), density, DO, pH, Temp, of water, and feed composition/conversion. Do not feed in the evening (allow for complete tank volume exchange between the last feeding of each day and dark). Sustainable fish load and feed rate also varies somewhat depending on type of plant species grown (e.g. leaf vs fruiting) and somewhat on the stage of development/maturity. Too many fish eating too much feed and respiring too much TAN for the size of the biofilter bed in current use is not advised. One could get away with this in the short-term but not over the medium- or long-term. pH; iAVs is dominantly (90-95%) Horticulture - by mass and economic value in most markets). Maximal fish production is NOT a goal nor advised. Vascular plants strongly ‘prefer’ (grow best) in range of pH 5.5 to 6.8 (extremes) and optimally 6.4 +/- 0.4 (variance range depends n specific species). Believe it or not. If one is satisfied with the results of one’s efforts, then that’s wonderful, really!. If one wants to improve one’s circumstance further, then consider accepting best-intentioned advise. Soil microbial ecology. Microbes evolved along with the plants they sustain/interact with, meaning they too benefit from pH in the ‘optimal’ range. In a ‘controlled environment e.g. greenhouse Pests and diseases: Take every prevention precaution possible (too many to describe here). A common vector is humans: limit and pre-sanitize all visitors and workers. Monitor for any/all developing problems continuously and have appropriate remedy available immediately. A gram of prevention yields many kilos of cure. Use integrated pest management strategies extensively (employ beneficial insects, bacteria, and plants). Use insecticidal soaps (Potassium salts of fatty acids) and plant-based extracts with care (minimize/eliminate contact with filter substrate) Maintain air temperatures and humidity levels appropriate to the plant species being grown. Shade, fogging, evaporative cooling can each be effective for cooling, either individually or in various combinations. Always provide ample ventilation and continuous air movement within a greenhouse. Above May Not be stated the best way possible: Its just what keystrokes I activated this morning. Any remaining gaps, errors or omissions are not intentional and regrettable.(and correctable). Questions to ask yourself - OR better yet, to share your responses to here: Is your water ‘clean’ or is it contaminated? (e.g. nitrates, phosphates, pathogens, …) DO you have/use an inert, well-drained sand (sharp SiO2 preferred) DO you flood saturate and then leave drained on 2+/- cycle during the day? Are you maintaining ‘system’ (water) pH in the range preferred by plants for optimal growth? Above pH 7.0 is NOT recommended. Do you have a ‘balanced’ fish load and sustainable feed input rate? Are you growing nutrient demanding crops (solely lettuce is not advised)? If you answered Yes to ALL of the above questions, then congratulations … you’re amazing and quite unique. I say that in spite of the fact that I will always insist that AP is a disease. Some diseases are curable, others are not. You’re Welcome. ============ PS: Yes, I am fully aware that focusing on plant production (minimizing fish to plant ‘ratios’) is viewed as blasphemy by many, if not most, aqua-holics. This is not a concern I have. No one is attempting to prevent anyone from doing precisely whatever they feel like, be that rational or otherwise. Don’t freak out or invent fallacies. I am describing what iAVs was intended to do, aka how it ‘works best’ (to date). What anyone who is NOT literally doing/using iAVs “feels†about claims and goals thereof is irrelevant to me. Do it or don’t. Your choice. Your life. ....... BTW: Not seeing is not believing ... and vice-versa If you do undertake iAVs, then please accept our advice in the spirit intended. My/our intention is for you to realize the best outcome possible, with the greatest cost:benefit possible. There is and never has been anything (positive) ’in this’ for me. iAVs has always been exclusively about you (others). That is all. No fee, No exchange, No refund. No apology.
    7 points
  9. Ravnis

    Ravnis' Sand Bed #1

    I have set up my first sand bed trial. It has been plagued by many problems as I have to uncover the greenhouse in the summer due to intense heat. Growth has been great, but my dogs have decided the sand bed is great to jump in and play in and have had to redo the furrows multiple times. I'm not using fish, but the sludge out my RFF from my main greenwater system and water from that system. I had major issues getting sand. I finally settled on "concrete sand" that was supposedly washed of fines and clay, but was not. The water becomes tan when it is disturbed. As far as cost, sand is dirt cheap as far as media is concerned, but it was about 10 times more expensive than if I had set up a similar size system with moving bed bio filter and sedimentation filter. It does not drain very fast and that is actually a great benefit. I do not have to run the pump through the growbed as often as I would a gravel bed. Seedlings do just fine and I could get by with running the pump a mere 30 minutes a day in 95F heat and not have to worry about heat stress. The draw back at running it this way is nitrification is not that great. Maybe next spring I can give it a try with properly screened and washed sand and compare results. Since I don't have fish to worry about I don't have to worry about whether nitrification is fast enough. The growbed fills up in about 2 minutes, but the minimum pump timing increment I have at this time if 15 minutes. So the flow is not the way as described in Dr. McMurtry details of his sand bed design, so any failure of the system I attribute to not finding a medium - coarse grade of sand. I was amazed at how difficult a task that was and went from sand and gravel yard to yard. The main benefit I can see so far is the ability to hold enough moisture so as not to need very much pump time. A tank with a moving bed bio reactor and filtration may be the best way to utilize this system as part of a low energy system. I have been able to observe the formation of a layer on top of the sand that I am currently believing it is the "Schmutzdecke" layer. As far as the water clearing up and becoming clean that has not happened. This could be completely due to having to keep it from overflowing I have the drain open so water can flow though it while the pump is running and then an amount of water percolates through the sand and drains through the bed over the course of ~2 hours.
    7 points
  10. Aufin

    iAVs in Florida

    A little less than a month with the new iAVs and what little I've put in the bed looks happy. Tomatoes, peppers, cucumber, cantaloupe and a small bean plant I rescued from another bed that wasn't doing so good. Finally got the weather protective top on. Want to grow some okra, but from past experience they have larger root balls than I want to deal with in the main bed, so I built a small 2ftx4ft iAVs bed dedicated just for okra ....... for this season. Which got me thinking. Why not build a few more small iAVs beds instead of disrupting the entire large bed when changing out plants with large root balls and disrupting the furrows. Something to think about. Any thoughts, Gary? Since I no longer am running a gravel F/D system, I have an RFF and a homemade swirl/vortex separator I no longer need. The RFF was inline for a couple years. The Vortex I made, but never put inline. It has been tested and doesn't leak, has a conical bottom and drain line, but not drilled for water in or out. Both are made with 55 gal blue barrels. If anyone's interested, PM me. Question for anyone growing viney vegs. I've seen photos of cuces, tomatoes, etc being trained upward on string, rope, cord, whatever. Is it best to just train one or two strong vines from the plant and nip the others off, or train everything into a bundle along a couple strings?
    7 points
  11. My first trials with sand media filters (1984) placed a small 'tupperware' dish pan (approx 12"x16"x8"deep w/ a dozen or so small holes (~1/16th") bored into bottom edges of the side walls, not into the bottom itself). Filled it some sharp quartz sand 'appropriated' from a glass-maker friend. I placed this container of sand on a shelf which over-hanged a 80 gal tank of fathead minnows (keep to feed African Knifefish, Papyrocranus after ). I found that I could then eliminate the pair of three-stage Eheim canister filters I had been using and have even better water quality. After a month or so, I planted some leaf lettuce in the sand, then dill, chives, spinach, bush beans ... and then also started using furrows and reciprocating biofiltration (aka 'flood& drain' w/ an interval timer for the pump). Worked great from the start. Proceeded from there. The rest is history - regrettably. So, small can be beautiful, as well as practical, and a wonderful tool in your learning kit.
    7 points
  12. The use of carbonates or hydroxides raise the ph alkalinity.... kh & gH are often referred to or measured in degrees of "alkalinty", or more correctly Calcium Carbonate They refer to the ability to buffer pH... It is commonly the case that source water with high kH and/or gH... also has a high pH.... and are often referred to as "alkaline", as opposed to "acidic"... Carbonates will raise kH in conjunction with pH... and could raise gH.. if used in very large quantities... but both your pH and kH would be off the scale, and your fish and plants probably dead... General hardness (although expressed in degrees of carbonate)... is a measure of the "mineral" content of the source water... (usually described as "hard" water)... and usually reflect Calcium, Magnesium and/or Iron.... and any others Nate's video was somewhat confusing.. and taken out of context... he was referring to how high carbonate content in high pH/hardness source water systems can be problematic.. as often seen.... and frequently posted.. It's not so much the "carbonates" that are esential in a low pH situation.. such as when buffering is required.... but more the provision of a "carbon" source for the nitrifying bacteria... In low pH scenarios... (which by definition essentially mean very low, or near nil carbonate buffer capacity)... the bacteria don't have the carbonate as a carbon source... (as they would in a higher pH).. instead utilising the CO2 in the system being produced by the fish.. which otherwise would form carbonic acid.. and drive pH even lower... (again related to the fact that there is no buffer capacity) People suggest "hydroxides" for pH control... as commonly used in RAS... for the reasons posted above... and because that leaves the pH within a preferred range for plant nutrient uptake... 6.2 - 6.8... Others prefer "carbonate" compounds.. or even quantities of "shell grit" or even limestone... to maintain both a more "stable" pH... but also a more "neutral" pH closer to 6.8 - 7.4... Diurnal swings in pH are more a feature of algae... and significant in pond based aquaculture... but negliable in most backyard aquaponic systems... But yes dosing with excessive hydroxides (or carbonates for that matter) in a single dose could certainly result in large pH swings... and the "Kalkwasser" drip methodology was invented as a means of constant pH buffering (equated to feed levels).. for this purpose... Many ornamentals, corals and marine crustacea, molluscs etc... require a "hardness" content.. that's more related to Calcium for shell integrity... And as such it's "normal" for aquaria circles to recommend "minimum" kH levels... but that's also in conjunction, even if not expressed... with pH ranges above what is typically used with freshwater fish... and certainly in AP systems... (Quick and nasty off the top of my head.. I'll come back and review later)
    7 points
  13. Depends on the scale. I have used them in the past. UV is very expensive at large scales. If you are using pure oxygen, better to use an Ozone generator then no matter how dirty the water gets, it still gets nuked.... I ran across the concept of keeping your math all in the same units through the process in primary school.... lol Not quite. If you want to convert the result to Nitrate (NO3) then you will need to multiply it by 4.43 but it is not necessary because you are looking for nitrogen in any forms. If you assume the contant addition of feed, then you can also assume that some of that input nitrogen is in different states of oxidization within the system at any given time. If you put in 1 gram of nitrogen as protein, you convert that to nitrogen by multiplying it by 0.16, then account for assimilation by the fish, loss through solids and uneaten feed (multiply the protein by 0.092 accounts for all that). The remaining nitrogen is carried through all of the processes (with loss to cell mass). You only want to know what nitrogen is put into the system and how it is taken out, what compounds it is in is irrelevant. Example below I published two years ago on my site: The organic nitrogen has to go through the nitrification process so yes, but again not relevant.
    7 points
  14. Well finally back home!... The end of a huge effort, time to relax for a few weeks then onto the next mission, another country a much larger system. As updates come from this project I will try to update you all.
    7 points
  15. Jon Parr

    The Viridis System

    Yeah yeah, I get distracted so easily. And I hadn't formally released interest in V until very recently. So, I will proceed here as myself only, and let everyone know that I have no involvement or affiliation with V (I really prefer not to even use the word, so V will have to suffice). I speak no ill nor favor towards V, and offer input on this thread merely for casual discussion and will use only hypothetical data...for the record. Now then, introductions are in order. I am Jon Parr, friend of many on this site, and an aquaponics enthusiast since fall of 2009. I, of course, had immediate ambitions of going commercial as is the case with so many newbies. I suppose most folks either wise up to reality, or perhaps lack ambition to proceed, but I couldn't let the idea go. I researched a lot of info from a lot of sources for a long time, and ultimately decided I would in fact pursue commercial AP. I was in construction at the time, specifically granite counter-top fabrication. I have owned my own businesses of the construction sort since I was 20 (now 41). I had a hell of a time quitting construction, as I have been around here for a long time. I still get calls almost daily for granite work, even though it's been two years since I was in that biz. In addition to being ready for a change, and taking the brunt of a declining construction trade economy here in Cali, I had carpal tunnel pretty bad and getting worse. The doctor told me if I wanted to keep the use of my hands I would have to quit my granite biz. No arguments from me. I quit taking new jobs in summer of 2012, and it still took over six months to fulfill my contracts. On Jan 1, 2013, I considered myself a commercial aquaponics professional, not because I was making money doing it, but because I refused to make money doing anything else. Sometimes the only way to commit to something is to simply not commit to anything else. It helps to have patient and agreeable wife. For those who don't know my wife, she is the best, kindest hearted, forgiving, easy-going, thrifty, generous, and most beautiful woman on the planet. I couldn't have done it without her and my awesome kids. Thank you very much, Parr family. The first few months of 2013 were devoted to putting together a business plan. I made lease arrangements for 5000 sq ft of greenhouse space of a flower business in Watsonville, CA, with the agreement to build into 5K sq ft more each month until I occupied the entire 320K sq ft. Watsonville used to be home to a very lucritive flower business of over 40 multi-acre greenhouses. However (and it's a whole 'nother story), the flower market crashed and there are a lot of empty greenhouses. Rent for very nice greenhouses here is only $.05 per ft per month. So 5000 sq ft is only $250. Easy peasy. I spend more than that on beer. Each bay of 5K ft holds 10,800 raft holes, plus fish and some wicking beds. So...at a buck per hole, there was potential for $10K of sales per month, and this was a very easy task for just my family to care for. Seriously folks, the math and reality for commercial aquaponics on a family farm scale is very favorable. I scrounged enough dough of my own to buy the materials to build the first 5000 sq ft. and that was it. No buffer, no back-up, no room for error, and no choice in the matter So...enter the biz plan, which called for $250,000, which covered 6 months of expansion with no sales income at all. I was committed to starting biz on my own with or without capital, figuring I would either get lucky and not need it, or any progress I did on my own would only add value to the biz plan. As it turned out, I never pitched my project to an investor. The money found me before I had the chance to go looking. I met an individual who convinced me to take him in as partner, complete with access to money and fantastic contacts. I had avoided partnership for my whole life but I knew the potential of this aquaponics biz was enormous, and wasn't opposed to help. This was a critical mistake. I'm not actually against partnerships in general, but to do it again I would have structured things on a progression of time and vested interest earned, not freely given (with a cherry on top, for hell's sake). I agreed to lease the site in March 2013, met my would-be partner in April 2013, and agreed to pair up if he could raise $250K of seed money and cover my role in the company half of the time. Now to be clear, I know of only one partnership that I would consider "good", and that is a couple of contractors in town named Craig and Rick. Now Craig and Rick started business as high school buddies. At some point fairly early on, they butt heads over something, tempers flared, and Craig split the scene, decided to part ways and take his family on vacation. Not surprising, right? Lots of partnerships end similarly. Well, after some time off with family, Craig realized he hadn't thought things through entirely, and was having regrets on bailing. So he went back like the "prodigal son" to Rick and asked forgiveness. Well, Rick had been suddenly responsible for double the duty during Craig's absence, and said "sure asshole, you cover the biz while I take some time with my family". What they discovered is that both of them were capable of running things without the other, and actually did better solo than together. So they agreed to each take half of their life off from work. Brilliant! Craig would enjoy life as if he had no stress for a week, a month, or even months. Went rested, he would overlap with Rick just long enough to get abreast, then take charge while Rick bailed for weeks, months, whatever. That is awesome, and is the only scenario for which I would ever accept a partner. My would-be partner agreed to learn everything I knew, I agreed to learn everything he knew, and we would overlap as little as possible thereafter. But alas, we were not of the same philosophy or ability, and this particular union was not destined to last. Anyway, that's all in the past now. So many people have asked how it is possible that I could get "fired" (for lack of a better term) from my own company? Well, here it is as simply as possible. After we partnered and got seed-money approval, the owner of the greenhouse discovered he had cancer and did not want to lease the GH, but rather sell it. We stopped building and started looking for another site to lease. However, the investor offered to simply loan the partnership the $2.35M to buy the GH. Wow. Sure, why not? So, the partnership bought the GH outright, with a debt now ten times larger than the seed money was to be. Looking back, I was excited and honored, and I neglected to revise the biz plan. It is very different to make interest payments on millions of dollars immediately, rather than rent at 5 cents per foot of modest expansion. We simply decided to expand and get successful much quicker in order to afford the greater payments. Now then, the seed money and the real estate loan came with 6 months of zero interest, and no payments, quite generous and honorable. We bought the place in July, making February 2014 the first month when interest payments would come due. Under the terms of the note, "default" would result in ALL SHARES reverting to the money man. A little strict perhaps, but not uncommon under the circumstances, and really, if we couldn't make the interest payments after 6 months, then there would likely be little to argue over anyway, right? Well, we did build and get very successful fast. The money man came to visit the site in February 2014, the first month of debt payment. We were lean, but on the verge of so many good things, and had over-achieved on so many fronts. He stayed for a few days, talked about payment leniency with my partner, and left town again. My partner told me he gave us six more months with no payments, though interest would begin accruing. Great!!! This would push off our payments until August 2014. No problem. This was the time we needed to turn the tides from construction to production. We got Organic Cert and Food Safety shortly thereafter, college food contracts, twelve distributors carrying our produce, ready for the spinnaker leg home! Then, quite unexpectedly to me I was presented with a default notice in May and stripped of my shares and all interest in V and the holding company A.G., with no "recollection" of the verbal 6 month extension we were granted in February. I didn't get it in writing. My bad. I take responsibility. Lesson learned. I was dumped like a cheap date, with no reserve in my personal bank account, voluntarily short on draws so as to not stress the biz, and a whole lot of personal money tied up waiting for finish line. My ex-partner is still there, signing documents as "president" (even though legally he was also stripped of his shares, same terms as I), and running the show now. You connect the dots. Okay, so to sum up, I am no longer part of V, and happier now for it. We were on the verge of insane expansion, so it would have been worse to have the same thing happen later. I was shocked, betrayed, hurt, dead ####ing broke, ashamed of my gullibility, and totally peeed. All the weirdness of previous months of behavior was suddenly understood. I don't know or care if V will carry what I built to wild success, or burn it down. Don't care. When one door closes, others open. I have since started a non-profit company devoted to sustainable ag and aquaponic greenhouses for schools. I think it will take wings pretty quick, but that's a story for another thread. I also have several well-funded folks competing for my next venture commercially, if I choose to do it again. I had a fun and rewarding experience for most of the last year. I learned more about the farming business than any other possible school, internship, or solo business could have ever taught. I made hundreds of life-long friends and contacts. I know now so much more about partnerships, corporate business, and finance. And I am now free to choose the next road I will travel. I'm going to have to sketch up some drawings to describe flow and concept, so I'll be back ASAP. Thanks for listening.
    7 points
  16. Aufin

    iAVs in Florida

    Finally got my system built and starting to season the growbed. The GB footprint is 4'x8'x16"deep. Made with a full 4x8 sheet of 3/4 plywood with a double layer of 2x8's on edge. Lined with a double layer of 5mil plastic. The sand is 6/20 coarse blasting sand bought from a sand supplier. A little outside the envelope recommended, but all I could find without going to a pricey custom blend (as if $86/ton wasn't already pricey enough). Took about 1 1/2 tons to fill the bed. Have a little left over to do a little tweaking if I have to. Running down the center on the bottom under the sand is a 4" black PVC perforated drain pipe in a "sleeve" to keep the sand out, but allow water to pass. On the drain end is a short piece of hard white 4" PVC pipe, installed through the wood, and reduced - after the elbow and below the bottom of the bed- to a 2" gravity flow drain to the fish tank. Everything is sitting on 3 rows of cinder blocks running the entire length of the bed to both support and to elevate the bed above the water level in the fish tank. The wood frame has a 1" drop from the fill end to the drain end. Sand has been somewhat leveled to the water after stopping the outflow to make the bed fill with water. The bed is fed with a pump on a timer through a 1" supply line coupled to a 2" dispersion T/pipe at the inflow. Don't know if it'll help, but can't think of a good reason why not, and being a little impatient, I accelerated the formation of the schmutzdecke (don't know if I spelled it right, but I like saying it) by dropping a small garden pond pump attached to a length of small neoprene tubing into the bottom of my now unused/disassembled RFF where lots of "stuff" had accumulated, and "painted" the furrows with the stuff. After letting everything sit and bake in the Florida sun, the furrows seem to be doing their job quite nice. Note to self - Don't touch the stuff, you idiot. Leave it alone. Gotta start listening to myself sometimes. As far as I know, the only other thing I have to do is make the little lady happy and give the bed a coat of paint. Sometime in the next day or so I intend to put a couple sacrifice plants in the bed to see how everything goes. Don't be expecting a lot of updates on any kind of regular timeframe. My work frequently takes me out of town, which is one of the big reasons iAVs caught my attention ...... Seems iAVs can run all by itself with minimal input and/or monitoring from me for a day or three sometimes if necessary. We'll see how that works out. Oh yeah, I have to build a cover for the system. Frequent rains here can do a pretty good job of ruining the raised rows. Probably forgot something, but I'll put photos up and go from there. Well, Hell ...... doesn't seem to want to cooperate with my computer to upload photos.
    6 points
  17. GaryD

    Demo iAVs System

    Hi, Last weekend, I built my first iAVs system. I'm describing it as a Demo iAVs since it's total growing area is about 4 square feet. Goals: To determine if such a small system can produce something worthwhile. I spend plenty of money on seedlings so it did nothing more than produce healthy seedlings, I'd be happy. Anything over that is a bonus for me. To use it as a functioning visual aid when describing iAVs. To evidence the simplicity of an iAVs build....and the ease with which an iAVs can be operated. System Description: The fish tank is of about 250 litres. The sand bed/biofilters are 50 litres each - and of about 4 square feet in area. The sand is filter sand that is consistent with the iAVs prescription. The water pump is a submersible pond pump - 1400 litres per hour. An air pump will be used to provide aeration for the fish tank. The flood and drain regime will be controlled by a digital timer. At this stage, I have been unable to find suitable fish.....but the search is ongoing. If I can find nothing better, I may use goldfish. I'm currently tuning the system......adjusting water flow, determining the appropriate flood and drain cycle times, etc...as time permits. I'm also working on a video of the system build as part of my "30 Projects" program. Gary
    6 points
  18. This is an extensive and up to date free publication of small scale aquaponics from FAO. It is a wonderful body of work. With 260 pages that covers topics from water quality to cost benefit, and includes a full DIY aquaponic build and materials list, it represents the best free knowledge on the net today. This must be shared throughout your networks, friends and anyone interested in aquaponics at home. A perfect manual and handbook to get anyone going in aquaponics at a small scale. Admins, uploading the file and pinning at the top is a great idea.
    6 points
  19. ande

    Our experiments with IAVS..

    Hi vkn I don't think "sand being the new gold" is unique to India. That is, when/if you require/request, certified ISO standard or equivilante, on the product spec. - guarantied inert chrushed granit sand agregate, and buy a relative small volume (wich these experiments are, on a industrial scale IMO) Transport is also a wery large cost variable, deepending on location, here in Norway it would be 50-70 % of the total m3 cost in large volume, like bulk in truck or tractor hanger loads. Rail is really not a option, other than in sacks, wich is the most expencive sand to buy, and also involves more loading/unloading/handeling (labour costs). This is not unique to iAVs, this is a known con factor, with any/all intermittent sand ( or other type agregate) filters The two big listed known cons, are their size (footprint), and transport cost of agregate, if not sourced on site,and/or localy available, when considered as commercial filters. River/beach sand quality/properties, is deepending on (source) as in the local geology, just as much as chrushed granite when it comes to acidity/alcalinity where it differs is nugget shape/form, and that again will also differ with location. Here Norway a lot of the river/beach sand has been formed by a number of recent iceages, so it is not round in shape, but more edgy like industrial crushed granite (chrushed by a 3 kilometer thik ice sheet) we have other variations more rounded by the seasurfs it is all abaout location location location (geology) and this is public free general information in most countrys (geosurveymaping). Small tabletop or backyard systems is easy match in most parts of the world you do to the small volumes involved, you just toss a few sacks in the trunk of your car or a get a few m3 bulk on a hanger. So is it worth it ? I'm not sure why you direct that Q to MMcM ? as far as I can see, he has a wery limitid tolerance on the sand properities in regards to acidity/alcalinity in his iAVs spec. wich he has stated so loud & clear, in this and other threads. You/me/we have to make that call from site to site, and see what will it mean in regards to total invest costs. In your case you could try to alter (lower) the the alkalinity with acids (might not work) you don't want to go that route, for some reason(s), thats fine IMO, your system & call. So you might have to chose crops that thrive in a higer Ph range you might experience plant deficencies and lover crop yields compared to those within the iAVs spec ? Does it have a negative impact on the aquacultur side ? does the higer Ph mean that you can grow more valueble fish species to compensate for loss in horticulture yield ? If I where to go down the commercial route here, I would most probably glance more towards the AQ side on the Ph issue. I know that salmonid fisheggs/yolksack fry, and crayfish, are much more sensitive, to low Ph/alkalinety, than the tilapia used in MMcM's iAVs reaserch/trials. I think that your "problem" would be my aim/goal, my system my call, regardless of IAVs specs. and the/any? negative effects, on the plant side It is all about defining the local spesific system goals & potential IMO at any level(size) of integrated agri/aqua -culture/ponics. These discussions, tend to drift in to a discussion about closed laboratory environemet trial system(s), more than discussing practical real life systems, located fully or partly outdoors expossed to the local natural environement. I would try the acid washing adviced (by Gary) on the cheap/local/available sand, in a small system (might be a one time operation) I would purchase a badge of the expencive sand and try it in a simmilare small system (is the better yield result better, as in worth it) Sidenote: Mathias vkn did not discover this now read back in the thread and you will see this has been a theme or discussion, boardering to war at times, and caused a lot of moderation (work) of the thread do to the agressiv/personal natur of expressing opinions, on this spesific matter, hard for me to understand how any, that have read this thread could have missed it, even after all the moderation(s) Again vkn thanks for all your reports on YOUR experiments with iavs, I really enjoy following your cronicles please keep it up. Good luck in your continous efforts on all the projects cheers
    6 points
  20. Ravnis

    Please don't feed the Bears

    There have been numerous threads that have been derailed by people with an agenda to make others look stupid, cast doubt on others abilities, or just cause strife. I don't claim to know what motivates people to attack others, but it happens. I know, I know, Moderators are supposed to fix everything. I wish we as moderators were omnisicient , wise , and beings of great intellect, but alas we are just ordinary folk trying to keep the peace the best we can figure out how to. This is where we as the Moderation team have one simple request. When insulted by someone that is trolling, please don't respond and feed their ego. Most of us have much better things to do with our time than participate in backyard tinkling contests. Don't feed the bears and they will starve or find new hunting grounds.
    6 points
  21. Mark McMurtry

    iAVs in Oklahoma

    I find it somewhat encouraging that those who are operating systems at pH 7.4 or above still manage to represent their growth rates as acceptable. I say 'somewhat' because the bummer (for me, them and everyone else) is that until/unless they correct for this, they'll never actually know what is possible in productivity terms. I can't attach a specific metric to the difference you'd likely realize, however I'm inclined to suggest one would see at least a virtual doubling of productive (growth rate) if not three-fold. Which doesn't even address the nutrient availability issues, most notably wrt the macro-nutrient Phosphorus, but also wrt Boron, Copper, and Manganese. If one is pleased with one's results arising from pH 7.4 conditions, then you'll be literally doing 'cartwheels and hand-springs' at pH 6.4. Believe it or not, totally your call. Not intending a chemistry lesson here, in layman terms high pH (>7.0) means low hydrogen-ion availability. Adding an acid adds hydrogen. This hydrogen boost will neutralize bases (such as CaCO3 molecules). Once the H interacts with the base molecule(s), its no longer an acid. Neutralization 'means' that the acid is no longer acid and the base is no longer basic (caustic). Any chemists out there need not chastise me for this deliberate over simplification. I'm saying that just because one adds an acid to your water does not in anyway suggest that the acid is still 'active' ('hangs around) after having contacted (neutralized, reacted with) a base. To many here this is may be way too obvious, so I write this in simplest possible terms for those to whom this might be news. CaCO3(s) + H2SO4(a) => CaSO4(s) + H2O(l)+ CO2(g) CaCO3(s) + 2HNO3 = > Ca(NO3)2 + H2O(l) + CO2 Ca(OH)2 + 2HNO3 +> Ca(NO3)2(s) + H2O(l) + CO2(g) Note: all these, and other similar, reactions are highly exothermic (generate heat) btw, CaSO4(s) is water soluble (both Ca and the SO4 will become available to the plants) per Wiki Solubility in water 0.21g/100ml at 20 °C (anhydrous)[1] 0.24 g/100ml at 20 °C (dihydrate)[2] Solubility product(Ksp) 4.93 × 10−5 mol2L−2(anhydrous) 3.14 × 10−5 (dihydrate) [3] - as too are all the oxides of Ca, tmk ++ Random links (top hits) with info on: Calcium's role in botany: http://aob.oxfordjournals.org/content/92/4/487.full and wrt Sulphur (sulfates) : http://www.ipni.net/publication/bettercrops.nsf/0/A04D690D24FB9E6085257B7200552E54/$FILE/BC%202013-2%20p10.pdf (no, I didn't read these articles past the abstract, posting merely to demonstrate that vast technical resources are instantly available to those who want to know) ++ PS: Gary's going to chastise me - in about 2 hours time - for having the effrontery/temerity to offer horticultural context to professed aquaholics
    6 points
  22. kellenw

    Why Aquaponics?

    I LOVE aquaponics... ...but... I also believe in using the best tool for the job at hand. Sometimes other tools are better, depending on what you're trying to accomplish. When we approach AP objectively, instead of applying the somewhat cult-like obsession that so many other sites apply to it, we better understand its place and its appropriate applications, rather than trying to make it out as the "be all, end all" solution that results in a lot of disappointment for newcomers once they realize the limitations it has versus the promises they were told (elsewhere).
    6 points
  23. I've found that most of the people don't really want any real discussion... they just want affirmation... that they're right.. and deserve to be "liked"...
    6 points
  24. Then the easy part of the plant growth...... let me make it simple for you. The protein in say a lettuce variety is 20% (make my life easy) Assume the lettuce is being sold at 200 grams Meaning you have 40 grams of protein in that lettuce Reverse the Protein to Nitrogen calculation Reminder that calculation is P / 6.25 or P * 0.16 So this lettuce has 6.4 grams of nitrogen stored in it The lettuce grew for 10 weeks (70 days) (making it easy for me) Without going into the mass growth of the plant the average nitrogen for that lettuce per day is 0.092 grams If I wanted to grow 1000 lettuce in that period I would need 92 grams per day of nitrogen put into the system If my feed has 80 grams of nitrogen in it per kilogram and we assume 62% of is available for the plants after processing I am left with 50 grams of nitrogen per kg of feed for the plants per day I would need 2000 grams of this feed per day. 1000 of these lettuce at a spacing of 25 per square meter I will need 40m2 to grow it in. This would give me a feed application rate per square meter of 50 grams/m2.... close to UVI huh? The numbers are very loose but you will get the idea... simple huh.
    6 points
  25. On the subject of mass balance, I would just focus on the nitrogen. You are calculating on different equivalents. If you are saying there is 12 grams of TAN (total ammonia nitrogen) then converting to Nitrate but not using the equivalent of the ammonia nitrogen your calculations will not be right. Your Nitrate nitrogen is measured as that, not converted or you have to convert the equivalent for the ammonia as well. Example the molecular weight of NH4 is 18.03851 and NO3 is 62.00501 divide the NO3 by the NH4 and you get a multiplication factor of 3.4341. Same with the nitrogen equivalent NH4 is 1.29 and NO3 is 4.43 you get the same multiplication factor. To get to those you divide the total molecular weight of the compound by the atomic weight of the element you are looking for. Example NH4 is 18.03851 and Nitrogen (N) is 14.0067 divide the two and you get the equivalent of 1.28784....... blah blah blah lol It is the Nitrogen you are looking for example when you buy a fertilizer it may be called Ammonium Nitrate but it tells you how much Nitrogen is in it not how much nitrate is in it. Both ammonia and nitrate have one atom of Nitrogen..... it does not create any more magically. EG - NH4 + 2O2 -> NO3 + 2H +H20.......... there is no extra nitrogen..... you will lose about 2.5% to cell mass... nitrogen is nitrogen no matter what compound it is in... So... if you keep all the same units through your calculation it will go easier for you. EG: Ammonia nitrogen is 12 grams per day Ammonia Nitrogen after cell mass (2.5%) 11.7 You want to keep 200mg/L of Nitrate nitrogen Lets forget the ammonia and nitrate... You have no nitrogen in your source water? (check that) You have no passive denitrification (only in the fish system) In 1500 liters each day you introduce 8mg/L of nitrogen (at biomass)
    6 points
  26. I thought this would be beneficial for those planning new systems or upgrading existing ones. Feel free to let me know if I should change or fix anything. Thanks!
    6 points
  27. Finally! Great news. As many know the single most challenging part of growing in the desert next to the extreme climate, is water. Water here is mostly from the ground and most of it is not very suitable for farming due to the salinity. This requires expensive desalination plants and on this site, our water table is 1200 feet below the surface. The great news we are one step closer to adding another link to the sustainability of this aquaponic farm. Awaiting final testing for a waste water source which matches our entire farms water needs. This means we will have a zero water use on the farm because this water source is already used for food, then we use it for the fish (and cooling), the waste from the fish to grow the plants. Then there is one more stage to having the farm running on 100% waste inputs. (the final after that is renewable energy). I am absolutely stoked to be leaving this farm in the middle of the desert with it having zero impact on water use and the local environment and ecology. What a fantastic outcome!
    6 points
  28. Essentially, the "answer" is... start taking already available accredited educational classes within the aquaculture sector and/or horticultural hydroponic sector. Then, combine what you have learned from the two so to create what is called "aqua-ponics", which this is a quite expensive and not entirely reasonable route to suggest. As a broad acre grain Farmer myself, I have never attended horticultural school so to obtain my agronomist or entomologist credentials nor have I attended a vetenarian school so to know how to manage cattle livestock. Actually, the worst farmers I have met have been those with these credentials simply due to them not knowing business. Like I always have said... Growing is easy... Being a proper business manager is not something that is taught so easily with statistics nor data; I think this is due to the fact how "common sense" is dismissed within these sciences. Unfortunately, I find that many hobbyists have a high level of arrogance about them, which is why the statement is true when Paul writes, "last thing we need is more half armed passionate people with enough information to make them dangerous." Hobbyists tend to learn one narrow facet of an ideal and then stretch the ideal outside its original context. Then, these hobbyists start believing their own rhetoric in that thinking they hold the "experts" at a level of disdain since they can do better, such as is done by FAP and expressed by others (not going to name names, but got a few in my head), in the portrayal of "what is actually necessary?". As an example to help folk relate, look at the prevalence of Potassium Permanganate (PP) from a couple decades ago in the goldfish/koi pond hobby, back when PP was the most common reason for so many fish deaths since it is an excellent parasiticide, and to now where there are actual accredited aquaculturists and chemistry professionals involved in the goldfish/koi hobby stating exactly how PP should be measured, monitored, and controlled. Now, due to the increase presence from the accredited professionals, there have been fewer fish deaths attributed to the use of PP. The only way the correct material will be taught is when the accredited professionals step up to the plate. At the moment, quite excellent articles are being written by Mr. Van der Werf at his Earthan Group website and Bright Agrotech to clarify many issues and forums like this where there are other accredited professionals occasionaly expressing their sage point of view. I think this in it self creates quite an excellent "training" program even though it is not specifically layed out as a traditional linear training program. I think this, as described in my previous paragraph, is the begining in the refinement of the "aquaponic" hobby. Unfortunately, this refinement is not what is taught to those individuals looking for a more traditional linear training program until someone points out to them how what they have been taught is quite wrong, which is tough to do after all of the monetary investment given so to attend these training programs. The "aquaponic" hobby is quite young even though the idea of "integrate aquaculture" has been around for a while. This is much like the PP example that I previously wrote about in that PP has actually been around for a long time as a parasiticide in many industries, but the hobbyists were quite young with it and thus made many mistakes until the profressionals finally stepped up to the plate. Now, I think there are professionals steping up to the plate and doing what they can within the "aquaponic" hobby, which is quite awesome and very much appreciated. One day, these professionals will retire without jadedness to the hobby sector and still have great enthusiasm for their work in the industry; thus, hopefully become more involved in the hobby to the extent these inredibly refined training programs might come to light so to force a retreat of all of the bad information/advice back into the shadows.
    6 points
  29. Strider: The question is CAN we, not HOW DO WE. So my hypothetical, "best case" in fact answers the question. I will pursue the best of human nature rather than the cynical. I am fully aware of the terrorists, the political elite, the greedy, the evil and the sordid. I am also aware of the fireman who goes back into the blaze to rescue survivors long after he is too weak to go on; the teenage girl who sees an elderly couple struggling with stairs and carries their groceries for them; the star quarterback who take the down's syndrome girl to prom; the college student who takes spring break to Africa to dig wells while his/her buddies hit the party beach. I need not go on. Both categories represent 'human nature'. I've been to over 30 countries on 4 continents. I've worked with farmers, housewives, royalty, college students, craftsmen, hair dressers and more. We've dug wells, built gardens, repaired roofs, taught classes, offered medical care, buried the dead. I've never once taken a dime from Government or seen Government operate with anywhere near the efficiency of ordinary men and women of different cultures, languages, genders and races who join hearts and hands in a cause bigger than themselves. I don't need to defend my argument or 'theory'. I've lived it. I believe. I act.
    6 points
  30. Ravnis

    Ravnis Indoor IAVS

    My quick and dirty setup of an indoor IAVS. I repurposed one of my cement tubs. It has an overflow that should hopefully never be used, but it's there to prevent overflow onto the carpet that might result in being kicked outside without a doghouse. I'm using a 1 1/2" drain using a uniseal from Allied Aqua. The hole is covered with carbon fiber window screen material. It holds the sand in the grow well. Light is a Galaxy Hydro led grow light I found on clearance. Growth is 2 weeks and a few days. I had planted mesclun in the other row, but it did not come up. The seeds were about 4 to 5 years old, so that may have something to do with it. I replaced with more spinach seeds yesterday. Spinach seeds popped up 2 days after planting. I could never get spinach to grow outdoors, so I'm just tickled to death to get some to actually grow. It just would not come up in my gravel beds when I had them. Timer is digital timer and pumps 1 minute every 2 hours. Can see the algae layer growing even with just LED light. The bed does not get natural sunlight. I had the light to low at first and some of the leaves burned. It's hard to tell from the pics. I rigged up a hanger and have it about 6" from the plants and plants are still growing.
    5 points
  31. As some of you know I hatch, feed train, and grow out gamefish to trophy size for the taxidermy and replica fish industry and I'm a fish taxidermist myself. I've done everything but beat fish farmers over the head to show them this is a viable sideline for their fish to no avail. Finally decided I had to do it myself about a decade a go. One type of customer is the taxidermist that needs large natural specimens to mount for state, national, and world competitions. As those of us that are anglers know you can't just go out anytime and catch a trophy fish in public waters unless you are lucky enough to live somewhere where that is common place. The following two fish won first place at the national level. The very latest is this brook trout raised in my trout pond and mounted by Mickey Bowman of Oklahoma. This brown was also a first place fish a few years ago and mounted by Frank Kotula of Pennsylvannia, USA. Needless to say I have a waiting list for large trout and run out of them very quickly.
    5 points
  32. Here is another video story kindly produced by Krishidarshan, DD Malalayam, on 27/10/2016 about our Nanniode Aquaponics commercial unit. Please have a look at this. This is iAVs project D. This program features my brother Jayakrishnan and family who are taking care of Nanniode Aquaponics commercial aquaponics facility. the largest of its kind in India this far. At Nanniode Aquaponics, we are getting ready for new crops. From a mono crop (tomatoes) trialed in the first season, we are now looking at about 8 different crops at this facility as per local community sale requirement. More updates will follow. Your feedback/questions are always welcome.
    5 points
  33. Okay, time for an update! I've been slow in building this prototype system for a variety of reasons but am beginning to think it might all come together! Here is a look at it so far.
    5 points
  34. MT Mind

    Small iAVs in West Texas

    After searching for months to find suitable sand for a small iAVs system, and repeatedly failing to do so, I have settled on a less-than-ideal scheme to sieve the sand from a batch of decomposed granite. I was able to get a sample of the decomposed granite from a local vendor - recomtx.com - and have been experimenting with it a little. The raw material is granite gravel, sand, silt, and a little clay, with the largest gravel being 1/2" or 13mm. The clay content is small, but remains suspended in water for days, and there is a significant portion of mica grains that flake during the washing/sieving process. These flakes may be a serious problem as they settle in an iAVs, but they seem to be removed well by fluidizing the sand until they are carried out by the water; they behave like much smaller particles in the flow. There were no indications of bubbles during the vinegar test, but I did notice that the silt and clay settled differently in vinegar than in pure water. In water, the material settled out as you might expect, with progressively smaller particles settling to the bottom, and the cloudy clay suspended for days in the water. With the vinegar, the cloud seemed to stabilize early on, like a coagulant was present, with a defined boundary developing between the suspension and the clear water above. This boundary descended slowly, with the suspension becoming more concentrated, and a few little holes appeared in the surface of the clay, apparently where water from below was escaping the pressure of the falling clay suspension. I'll try to reproduce this and get some time-lapse to show what I mean. I tested the water pH before and after mixing in the material, and there was no change, so I'm not too worried about the vinegar thing. I know people like pictures, so here's a little "sand porn" of the pile I moved from the front driveway to the back yard patio. More to follow...
    5 points
  35. Yes parabolic screen often need a bit of "help" daily to get all the waste removed, however the bulk is instandly removed. btw even drums need regular cleaning, bacteria grow on screens, drains foul, nozzles block up etc
    5 points
  36. I used a modified Purina 5140 floating catfish ration with minimum 32% protein. The modification, at my request, was to not add the normal micronutrient 'fortification' and vitamin supplementation normally added to the standard feed formulation. "All plant nutrients were assimilated above deficiency levels. Tissue concentrations of N, P, K and Mg were not limiting. Calcium was low and S was high when the sole nutrient source was fish waste products derived from the specific feed formulation utilized. Micronutrients were assimilated in excess of sufficiency, but no toxicity symptoms were seen. Irrespective of fruit yield, the metabolic products of each 1.0 kg increase in fish biomass provided sufficient nutrients for 2 tomato plants for a period of three months. Under reduced growth rates (and parallel feed input rates) typical of mature Tilapia [pmi of 600 g plus], K became limiting. Alternations in fish-feed composition (mineral nutrient content) which better meets plant requirements and still remain within the range of fish needs were suggested (McMurtry et al. 1991 c)." [From memory, both Copper and Zinc were well in excess of the combined fish and tomato requirements. Other metals were basically ideal or in the upper range of sufficiency (from tissue analysis) - wrt the combined requirements of both crops. Sulphur was also available in excess and Calcium slightly deficient but not limiting] Over the ensuing 25+ years, feed manufacturers have allegedly formulated chows specific to tilapia. I have no clue if this is true or not (sounds like hype to me) or what would have been modified. I've seen claims that feeds are better balanced and give better FCR (without any specificity. evidence TMK) - but for what (surely not for plants), why and how? Feed manufacturers do not provide elemental analysis as a rule. If one has a large enough order, they'll make whatever you want - for a price. Elemental tissue analysis is a costly, specialized effort (dedicated lab tech and equip). IMO, an important consideration for the commercial operator however the optimum levels of residual micronutrients will vary depending on the plant spp. cultivated. For the hobbyist and small-operator, I'd suspect most quality feeds will be in the ballpark for most elements and most plants. Note that tomato is perhaps the most demanding of crops (a main factor in our selection). Most crops have a fairly broad range of availability/assimilation between deficiency and toxicity levels. Sufficiency levels fall between the extremes and should be more than adequate for most growers. If one is formulating one's own feed, well ... then you are just guessing what might be acceptable or not unless you pay to have whatever your heart desired analyzed. I'd wager that commercial chows (from the major mills) will be relatively well balanced and also much cheaper, ntm easier.
    5 points
  37. Leaf crops will do well. However, leaf crops require a small fraction of the nutrients that fruit bearing spp. do. Lettuce especially 'luvs' Nitrate to the point where it can even become toxic to young, old and immune-compromised people. Of the other essential elements, leaf crops tend to assimilate very little, so its not very effective at removing elemental accumulations from the media. In addition to that, lettuce has an extremely low food value. Some nutritionists claim that its even calorie negative in that it can require more energy to digest than it represents (in tissue). So, IMO, why bother. On the other hand, its extremely easy to grow - idiot proof one could say- and quick to show a result, and it's size is right for small systems. Also suitable to grow as the first crop in a un-established filter where N is immediately available but most of the other elements haven't yet been made (as) available since the microbial community is not yet fully established. However, I have grown tomato, peppers, beans, etc. in pristine filters successfully, but they'll do even better in second and third crop cycles. If you what to grow a more nutrient-dense leaf crop, then consider Spinach or Swiss Chard - even Beets (altho the root will tend to be small but the leaf (best part IMO) will do fine. All of these are great eating, IMO, steamed with some butter and dash of malt or red-wine vinegar. Wish I had some now. Do not grow legumes exclusively since they won't assimilate N from the water/media. As an intercrop (esp. along side N-'hungry' spp.) , beans, peas, snow peas all do great in sand. You can also make excellent use of a limited area by 'going' vertical. Trellises of various sorts do well for tomato, cucumber, squashes, (mini) melons, peas, pole bean, .... About the only thing that doesn't do particularly well in sand are root crops, such as carrot, turnip, beets, radish. The bulk-density is just too high for good radial expansion of the root. One can still get a crop but they'll tend to be small and narly (mis-shapen) - looking nothing like what you buy in a store - yet they will still taste fine nonetheless. Never tried potatoes since I suspect they won't produce at all and also 'cheap as sin' in the store. Most all culinary (and medicinal) herbs also do very well in sand culture. Hope this helps.
    5 points
  38. My father uses a dive right in and learn by doing it approach. I am a procrastinator who likes to research and consider the options and look for potential problems before I start (and practice). His approach works when things are simple and there is a low risk of failure, mistakes are easily fixed on the go. Mine works when one mistake can lead to complete failure. I think you will need a basic level of knowledge things like correctly priming and joining pvc pipe and using pipe fittings how to water test and what it means what chemicals when and how the basic nutrient cycle calculations on how big things should be to do the job You should also come to the realization that AP is not the holy grail, I had to go on a little journey and look at the flaws and gaps in AP to finally twig that my understanding of gardening/farming in soil was very poor. I now have a green thumb I can literally throw something at the ground and it grows. The fact that I have earned a living from growing stuff for 30 years and made hard work of it, when I could have done it easy and spent more time chillaxing with family and friends is a hard thing to swallow. But Hey! better late than never
    5 points
  39. Here are some pictures of the build of my 5 gallon RFS. The theory is to split the outflow from the fish tank between two outlets. One at the top takes most of the flow (80-95%) out to a filter tank (netting tank or other type). The Other 5-20% of the flow exits through a bottom drain or via a SLO. SLO picks up most of the solids produced by fish and leftover feed and feeds that very low flow to a Radial Flow Settler. The RFS can be down sized without compromising the removal of those solids thanks to the low flow through it. The 5 gallon bucket RFS makes it easy to handle the cleanout. My construction for the 5 gallon RFS can be seen in the pictures below. And here is a video of how to clean out the RFS. It helps if you close the outlet valve from FT, then open RFS drain valve so the level of water in RFS is below the RFS outlet pipe. Then remove stilling well bucket and with a pipe swirl the content. This way you get minimal leftover solids in the bottom of the RFS. Whatever solids that are left in RFS can be cleaned out by using a small cup of clean water and just swirl it in the RFS. Hope this is helpful to someone. Cheers!
    5 points
  40. This technique is perhaps not widely known or understood.. especially in AP circles..
    5 points
  41. Interesting to note the constant comparison to traditional ag.. they grow 4 crops per year then it gets too cold or hot and that is it.... we grow a gagillion lettuce in the same space in a year.... right so any protected cropping using any method, hydro, soil, buckets, garden beds, will do exactly the same thing all year round.... the production is not exclusive to aquaponics, it is the climate control that allows the year round production, not the growing system.
    5 points
  42. I have done more of a progress report type thread on the pond boss forum and on byap but since i am kind of new here, i do not have a thread on breeding sunfish. Instead of cross posting an entire thread, i figure i will gear this more towards a how to guide since after my second year i have had some fair progress and I feel like i have gotten the process down. When i say sunfish, i am talking about common north american panfish and game fish like bluegill, red ear sunfish, green sunfish, crappie and black bass (largemouth and smallmouth). They reproduce at different times and temperatures but the process is pretty much the same. The males use their tails to fan substrate and build a nest in shallow water. females visit and lay eggs males guard the nest and aerate the eggs for a few days. larva swim up out of the nest and filter feed on zooplankton until they get large enough to eat small insects and move up the food chain.. So far i have only worked with bluegill and red eared sunfish because i havent had mature LMB or feed trained crappie. I have acquired and feed trained some black crappie so I hope to work with them in spring 2015. I now have some 1 year LMB that i could try to spawn but i have little interest in trying to deal with the highly cannibalistic nature of this fish 1) at young ages and 2) managing breeders because as fish get older the females way outgrow the males. I dont have enough fish tanks or desire to grade thefry/fingerlings on a weekly basis. And then i would have to manage breeders at young adult ages when they are still small enough for an aquarium but unfortunately would not yet know what genetic potential they posses. bluegill on his nest video of female visiting nest bluegill eggs are a translucent jellylike haze similar with red eared sunfish picture of my red eared breeders this past year once the eggs mature and start swimming out of the nest they are considered larva. They filter feed can you see the 10's of thousands of bluegill in this picture? what if we make it a little closer, can you see them now? at this stage they are starving little babies and they need nourishment. They are too small to eat commercial feed, even if it is pulverized into a powder. The solution is... an algae bloom not the algae itself but actually the microscopic rotifers and other zooplankton that eat the algae. I made this algae bloom in about 3 days using an ibc, half filling it with aquaponics water, a couple of tablespoons of rock phospate and an air stone. Leave it out in the sun, the warmer the better. The first year, i lost all of the bluegill because i didnt know i needed an algae bloom to keep them alive the second year, i was able to keep 200-300 red eared sunfish alive in a 55 gallon aquarium by doing partial water changes with the algae bloom water every day. At this point, i recommend moving the fry to the algae bloom tank outdoors and not try to keep them in the aquarium they were born in. I was using the aquariums primarily so i could see/view/record the progress but the low maint approach would be to just put them in the algae bloom water. if it starts to die off add more rock phospate and just leave them for a couple of months. They will be hard to see but just trust they are alive. You can start adding some crushed/powdered commercial food at the two month mark but when you do so you also need solution for cleaning the tank. probably add it into a ras/filter of some sort and remove the large particals. You dont need to get rid of the algae bloom because they will continue to filter feed even into adulthood and it would be best if you dont completely filter it out. at which point you will be here. Unfortunately, i made a huge mistake which killed most of my RES fry in july. i needed a place for 300 tilapia fry and i put them in the 55 gallon aquarium with the red ears. They were about the same size so i figured they wouldnt eat each other and maybe would help feed train the RES. unfortunately, tilapia can filter feed too, plus they were eating commercial /powdered food... so the tilapia just competed with the RES for food. Regardless of that result, it's ok to mix tilapia and sunfish later in life. And when they are bigger they do help with crowding and feed aggression that is useful in feed training notoriously difficult to feed train fish like RES and crappie. In the below video of my indoor RAS, The darker fish are black crappie, There are about 20 of them eating commercial pellets with hundreds of tilapia. I didnt feed train them with the tilapia but their feed aggression and growth has improved once they had to start competing for the food. not sure why this last video doesnt show in the post but i confirmed the link is correct. finishing thoughts: 1) As you can see. Sunfish are every bit the backbone of the freshwater food chain that tilapia are and every bit as much prolific breeders. 2) Well respected pond management biologists will tell you that it is impossible to feed train crappie, or that they will not eat food from the surface... this is a misconception and not true. 3) large mouth bass grow faster than tilapia 4) sunfish are native to north america and can tolerate our wider range of temperatures that tilapia cannot. 5) i hesitate to state anything that can be construed as an opinion as a fact, but it's a fact that all of these sunfish species are considerably better tasting than tilapia.
    5 points
  43. Earthan Group

    0 phosphate

    I think it is just taking people a long time to come to terms with the mineralization process. Compost tea brewing has been around a very long time, it is just taking time for it to permeate the fundamentalists in aquaponics because the expectation is the media beds have always done this process for them without the need for a separate process to efficiently deal with the organic wastes. It is encouraging, following the introduction and wide acceptance of filtration (a long battle Gary will attest to), the acceptance of mineralization is gaining a foot hold. On top of that, it is positive to see separate loops are starting to gain some ground. Another year and we will see more sophisticated systems in the backyard that are not prone to the common problems the current methods are, especially as the understanding of the diverse microflora becomes better known in the wider aquaponics community. To help solidify this natural progression, we are best to encourage these conversations that look outside of aquaponics (as some people wrongly think of aquaponics as its own learning discipline), and embrace the wider ecological farming methods that are seeing great success across even the traditional farming methods. It is the understanding of "what lays beneath" that will underpin, not only aquaponics, but all methods used for farming. We are all striving for the same thing, chemical and pesticide whole food production. Regardless of scale, the future speed at which aquaponics develops will depend on the speed at which we visit and ultimately accept the past.
    5 points
  44. As I eluded to in my post on FB I will be releasing the full design to the world to shape, modify and improve. It just takes time is all.... and preparations to do this are underway with an expected release in March...
    5 points
  45. Thanks for the kind words and willingness to chip in financially, Crsublette! And Ravnis, your recommendation is spot on for our US based members. Thank you as well. Fortunately, we have been able to keep costs extremely low for maintaining and hosting APN. I do all the backend admin work as well as site maintenance gratis, so those things cost APN nothing. I also pay for our annual domain name registrar fees, which are minimal. However, Allied Aqua covers the bulk of our costs, including ongoing software fees, dedicated server hosting costs and hardware upgrades to the server. Allied Aqua has been a huge financial supporter of our site in recent years, and all they've ever asked for is a small unobtrusive banner ad on the site in return. APHQ (now APN) was founded as "The Independent Voice of Aquaponics", and we're keen to keep it just as Gary originally intended it. Allied supports that ideal as well. Prior to this sponsorship situation with Allied, Gary paid for all of the costs associated with the site, and the biggest thanks really go to him. Without him, APN wouldn't exist. Gary transferred ownership of the site and related domain names to me in 2013, making me the new steward of the site. He covered 100% of the costs up until then, since 2007. He's given a great deal of his time and spent a lot of money to support and preserve this community over the years. He still continues to give generously of his time here, which deserves recognition. I am planning to spend a fair amount of money soon on a substantial (and long overdue) site upgrade, new server and increased bandwidth capacity. Probably in 4-6 months. Our ongoing operating costs will likely increase a great deal at that point, but should still be quite reasonable. While I've given some thought to accepting donations, there really hasn't been a need for it up to this point. However, that may very well change in the future. I don't expect Allied to provide us with a "blank check" to do with as we please. hehe. If we were to implement a donation program, it would obviously be completely voluntary, and absolutely not required for participation in our community. I've been giving some thought to organizing APN as a non-profit entity. Most importantly, I feel it's my responsibility to ensure APN's survival in the event I'm no longer around or able to take care of it. Sounds morbid, but let's face it... eventually that will be the case for all of us, so it's probably worth at least giving it some consideration. If we were to take those steps to officially organize APN as a non-profit entity, we'd probably step up our role in outreach and education a great deal. What that would be exactly and how we'd do it... I'm honestly not sure. So far, I've been pretty unimpressed with what most "non-profits" in AP have done/accomplished, and I'm not interested in putting my name or the names of our community members on something that is sub-par in any way. I guess time will tell with that. One of those things that would have to be done right.. or not at all. Anyway, thanks again for bringing up the topic. And thanks to everyone who contributes to the knowledge base that is the Aquaponics Nation community. It should be a fun and interesting year!
    5 points
  46. Wow you guys are getting into it here.... let's see if I can add some clarity. Let's do a quick and dirty mass balance.... gorrd... One of the tricky things in this watery fun is the soil comparisons do not fit. Let's run with this: every 1 kg of organic nitrogen you need 32kg of organic carbon. I know that might not fit with some info, but work with me here. Now how much organic nitrogen and how much organic carbon is in your waste... That is a very soft number, meaning depending on your feed, species, temperature and how you feed the results will change. But, let's run the numbers just for giggles because in a backyard set up, not much can go wrong and any changes made are very quick to respond. What do we know about our poop...? We have a 80 grams of organic nitrogen per 1 kg of our selected fish feed We have a 400 grams of organic carbon per 1 kg of our selected fish feed We are feeding 5kg per day We have fish that poop 25% of the carbon in the feed (we are discounting the dissolved organic carbon) We have fish that poop 15% of the nitrogen in the feed (we are discounting the dissolved nitrogen) What are we left with? We have 12 grams of organic nitrogen in our fish poop We have 100 grams of organic carbon in our fish poop We have a C:N ratio of 8.3 Carbon :1 Nitrogen The above result is 1/4 of the bacteria's requirement. So you will need an additional 300 grams of organic carbon to make it work well in that scenario.
    5 points
  47. Jon Parr

    The Viridis System

    Hello Rupe. There are several things I would do differently if I were to pursue it again. Some mods I've tested and happy to share, others I'm still testing so I'll hold my tongue until I'm finished. And let me state for all readers; I realize that my methods of commercial AP are not the norm, and no doubt will invite scrutiny as Gary said. That's ok, please bring the questions, one and all. Many folks are followers, doing what they are told to do by those who know what they are doing. These folks also tend to go about a task with the idea that those who are successful before them have tried everything and the current methods are the best methods. I'm not one of those folks. I enjoy "building a better mouse-trap". I'm not opposed to copying exactly what successful people do, but I don't begin a task assuming that they are doing it right. I prefer to study the science, see how various folks have applied it, and see what evolves from there. That being said, I have studied methods a lot, and not all of the accepted "principles" of aquaponics are true, IMO. One major change, and a mistake I would have changed at V, was the drain pipe sizing of 2" PVC. As Rupe stated above, gravity thru 2" piping truly is the limiting potential of the flow, especially where there is low or no elevation change. Rupe, I assume by "trickle filter" you mean the horizontal blue bucket of rocks? If so, then yes I suppose there is a limit potential there, though it is not the bottle-neck in the system. Since there is 3' of fall there, even a 2" outflow would handle a great deal more than the 2" crossovers in the raft beds. The first area of construction was roughly 500 sq ft of raft, 50 sq ft of wicking bed, 500 gallon FT, and 500 gph of flow. This module was repeated 5 tiimes to fill the first 5000 sq ft of GH. It was calculated to have 50 fish of 5 lbs size in each tank. How quaint, all fives. My take on stocking density is 1/2 lb of fish per sq ft of growing area, maximum. Very simple and quite variable. And I didn't mention a FT size in that equation for a reason, I don't think it matters too much in a DWC system. Different fish, at different seasons, have variable needs. As long as they are comfortable, you're good. There are reasons for over-crowding, under-crowding, or offering hiding places. Suit the needs of your fish, but the growing area holds the filtration, or more properly the nutrient removal, so I give more merit to growing area/lb of fish than anything else. And, that is a maximum, meaning you will be accumulating nutrients unsustainably at that full density. The idea is that when you harvest your fish, there will be a surplus of nutrition to offset the lack of production of the next fingerlings. It will average out over the season. And everybody, don't stress over it. If things get too rich, dilute it. If things get too lean, spike it. All good. In reality, a big system changes slowly, and the water can be blended from one bank to another, or stored aside, or whatever. Rupe, in the diagram above the FT volume was turned every hour. Our system was young, relatively speaking, so DO was seldom challenged. An additional water pump could be placed in the mesh-tank and route straight to the gravel bed if needed. This would increase FT turnover and solids removal, but not DWC flow-rate. This was done on occasion at V, and would be plumbed as standard OP from the outset to do it all again. In fact, this short circuit of flow gives one all kinds of options. The DWC could be taken off-line without changing the dynamics of the aquaculture (for a while, anyway). This plumbing allows for possible fish treatment without subjecting the DWC, or perhaps different pH, temperature, or nutrient management between fish and DWC. I'm touching on model alterations currently being tested here, but so far so good.
    5 points
  48. I just checked the clock on my screen. It said, "later". Ta da (insert rim shot here)
    5 points
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