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Toga last won the day on September 6

Toga had the most liked content!

About Toga

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    Tweed Coast Hinterland - Australia

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  • Interests
    Aquaponics, Aquaculture

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  1. Hi Ande, Thats really interesting regarding bitterness and freezing to release the sugar content. We have many 'edible' berries here too, but most are beyond bitter... might try freezing some ! Cheers Toga
  2. Hi Hooked, Yes, my winter water temps only drop to 12-15c for a very short period. It is not uncommon practice for those with larger systems to cycle 2 species per year. Warmer water perch, cod or barramundi during summer months and a cooler water fish like trout during winter months. Cheers Toga
  3. Hi Hooked, welcome to APN. Sounds like another interesting build, and now move. Ive never needed to heat during winter here in OZ, so can not offer too much advice. House insulation rolls have been used to great efficiency, if you can get them at a good price. Cheers Toga
  4. Hi Tam, I assume you put a ball valve on because the water was stirring up the sand on top to much ? So you turn it down a little ? I note you also put some material on top of sand to prevent it stirring up. The water flow needs to be maximum. Open the valve completely. If you put a "T" piece on the outlet hose it will: a) Minimise sand disturbance b) Divert the water into 2 directions c) Push the water across the sand (Not down into it) d) Even water flow through a maximum surface area I am not familiar with that test kit brand. Do you have a friend with his own test kits ? It would be advisable to do some tests using a different kit. Test liquids can become inaccurate as they age. The same brand is OK... we are looking to check the accuracy of the results your kit. Cheers Toga
  5. Hi Tam, In my view, these are individual things that I see, that when combined, create the issues you are encountering. 1- Fish per Volume (Species dependent) 800ltr tanks are good for approx 10-40 fish intended to grow to a reasonable food fish size. 2- Grow Bed Water Flow I believe the water is channeling from the hose outlet, through only a very small amount of sand area near the hose, then straight out the bottom. Thus only a very small percentage of sand is being colonized by good bacteria. 3- Total System Water Turnover A 2000lph pump, pumping 1 meter high from fish tank will have a reduced flow rate - perhaps as low as 1200lph (pump model dependent) 1 pump cycle of 6 minutes ON = 120ltrs ------- X 8 daily cycles = 960ltr/day Although I am not super up to date regarding IAVS recommended water volume turn over rates, only once per day seems far to low. I have always aimed for a minimum water turn over of once per hour / 10 times per day, in my non-IAVS systems. I would consider the following: A) Instead of only 1 hose outlet pumping into grow bed, perhaps increase this to 3 or 4 outlets. B) Instead of the hose outlet in the middle, place the outlets around the outside edge of grow bed. C) Instead of 6 minute pump cycles, increase this to 20mins On / 60mins Off... or more. D) Keep fish feeding to a minimum whilst mortality continue. Cheers Toga
  6. Hi Tam, Excellent response with quality info, thank you. This latest info continues to add weight to (add data confirming) my original thoughts and opinion regarding bacterial issues. I will add a detailed response *EDIT* In the morning**, however, I have one more fairly critical set of questions. Regarding the drain from the grow bed... A) Is the drain located in the centre ? B) Do you have a stand pipe / strainer raising a little from the bottom ? If so, How high is it from bottom ? C) Can you describe in a little more detail how you made / setup the standpipe / strainer and/or how you prevent the sand from draining into the fish tank ? Cheers Toga
  7. Hi Tam, Sorry to hear of more issues. So far your pics do not give me an accurate idea of your whole system setup. A) - System Layout / Specs Layout of growbed looks circular. What is the Depth ? Where does water go in ? Where does it drain out ? Where is the fish tank ? Shape & Depth ? Where does water drain in from growbed ? Where does it pumped out from ? (location of pump inside the tank) What water volume does it pump per hour ? What are your pumping cycles ? Do you pump at night also ? .... OR Only pump cycles at day time ? What grade is that sand ? .... OR ... Is it a fine 2-3mm crushed gravel ? Your excel file data suggests yet more questions need to be asked. The lack of daily test results makes it more difficult to track, trace, identify and resolve issues as they arise and recede. B) - Water Testing What testing methods/kits do you use ? (Liquid, digital, powder, tablet - What Brand/s ?) How old are they ? Can you do all tests at same time and post a picture of all the results ? C) - "OXY - YES" Please explain this notation in your data file. Is this additional O2 from compressed air cyclinder ? ... OR Is it from an Air Pump ? - OR - Blower ? Is "OXY" on any type of daily cycles ? ... OR "OXY" is on 24hrs day ? D) - Importance of Test Results Have I mentioned the high importance of accurate, daily records ? Oww... Yes, I have. It is almost impossible to accurately determine where your system sits within all the potential Nitrogen Cycle scenario's. I note you have 3 systems, but data for only 1 ? You should test each system every day - test everything - and record the data separately. 3 individual systems = 3 individual sets of water test records. E) - Importance of Test Results You current data points out an interesting piece of information and raises another question. Are you doing anything at all in the slightest bit different between the 3 systems ? System 1 mortality is much lower in this round of issues. It is still my view that you have rampant bacterial issues on several fronts. 1) Your Nitrogen Cycle (bacteria) is not / has not cycled correctly 2) If the current fish mortality look the same as previous - ie: bleeding into fins, redness of tissue I would recommend that you consider; Doing all tests again - on all tanks - record each tank separately - and post pics & data Reduce the feeding portion a little (for the short term) Do a 30% water change on each tank. Consider adding another 1ppm of salt to each tank. Post a couple pics of any future mortality. Cheers Toga
  8. Hi Tam, OK. Keep us updated. We all would be interested in seeing some pics of your setup. Sorry for my bad use of the word "investment". I have no "investment" here... we all offer our time and info for free. I was making an example of how sometimes in life everybody needs to consider what they will get in Return for the Investment. Sorry for any confusion. *Example* If you invest $100 on fingerlings + $100 on food + 100 hours of work + $30 on electricity BUT your return is only 2 kilos of fish a few tomatoes and lettuce. Sometimes when faced with this above example investment... sometimes it may be best to cut losses and start fresh. Such example investment, in my view, ought potentially return 50-100 kilos of fish and multiple 100's kgs of veggies. *End Example* Cheers Toga
  9. Hi Tam, That is great news ! .. and in such a short period of time ! Your timely interventions have shown their merit - Well Done ! Stopping mortality was priority #1 I am away at the moment and do not have time to comment in great detail. Perhaps someone else will add their thoughts too. I would advise caution adding too many fish at once, so soon at this point in time. Because of the new systems and issues thus far, and still existing issues. Your plant issues are multiple: Extremely stressed due to system issues, Nutrient lock out due to pH and now pests. In many cases I have myself had to weight out the: current investment -v- required investment -v- potential return. In this instance it is my view that you may be best served by removing and destroying what plants you have and allowing the sand itself (bio-culture) to continue to mature... add some plants in 7-10 days perhaps. Cheers Toga
  10. Hi Tam, Hoping the past 48 hours has seen a turn around in your morality issues. Cheers Toga
  11. Hi Tam and VKN, To add further clarity, freshwater nitrification bacteria have a much higher tolerance to salt than almost every species of fresh water fish and most disease bacteria. 7-9% Salinity levels are used in waste water treatment plants with zero adverse effect on the nitrification bacteria (microbe) life cycle. However, at 9% salinity, they are much less effective at nitrification. **EDIT Regarding Salinity** 9% Salinity = 90,000mg/l Remedial Recommendations of 2-3mg/l = 0.0002% - 0.0003% salinity Yes, salinity levels can and do influence plant growth immensely. Some plants simply die @2mg/l, others tolerate it but grow very poorly.. most fruiting plants hate salt. It is my view that if you do nothing and do not intervene with some sort of mitigation process, your stock losses may be significant. Have mortality rates decreased since you started water changes ? Cheers Toga
  12. Hi Tam, Good work keeping records, they are key to good success when you understand them well. Take time to study, understand, compare seasons, success and failures of your records. I note you have NH4 record as well as NO2/3. Due to the very low readings in your results, and the short time period from setup, suggests to me that your total "N" cycle is very shallow, very low... meaning the bacteria culture is very small and not very strong. The cycle values that I indicated above, are perhaps higher than what is actually required to establish healthy strong bacteria. Below is a quick google image of what I mean. Take your records and make a similar chart and compare them... Do you see the difference ? Can you see what I refer to as being a "very shallow cycle" from your records ? I note you make reference to "Tank 1", "Tank 2" and "Tank 3". Are these 3 tanks joined together to the same grow bed/s ? ... OR Are they 3 separated tanks each with their own separated grow beds ? The answer to the above is important to many questions about future management... but it is also unimportant to my next point of note: Disease Mitigation - (This is why adding salt is good - search this forum) Toxic water, No/low/unhealthy bacteria, burnt/sick/dying fish, very high water temps... All of these dramatically increase a) Disease Potential, b) Disease Verility and c) Disease Transmission Maintaining farm hygiene is paramount. - Sterilize your nets (soak in very strong salt water works OK) **EDIT** Followed by drying in the sun - Wash hands and arms when working in different tanks - Do not transfer anything between the tanks or grow beds - Remove and dispose of mortalities immediately and regularly One last comment for this response - I note your pH has risen since you started. a) What is the pH of your source water before you add it to your fish tanks ? b) Where is this source water from ? (ie: A dam, river, well, bore, city tap water, collected rain water) c) Do you store your water before use ? and if so - What is the material of the container ? (ie: plastic, concrete, earth dam, rubber liner) c) Did you pH test your sand before purchase/use ? Cheers Toga
  13. Hi Tam, I do not feel the SiO2 is a major issue here. I believe the culprit of your issues is NTS (as I call it)... New Tank Syndrome... and this is why I believe this to be the case: You added fish in just 3 days. Even if you did jump start the "N" cycle... and even if your water is 32C, the nitrosomonas and nitrobactors would still require 8+ days to cycle from NH3/20mg NO2/50 NO3/150 to being a safe, cultured bacteria colony. I note you did not supply ammonia readings. Being the initiating and most toxic water parameter of the nitrogen cycle, in my view, is the highest needed water test and ought be essential in your test kit bag. Being in Vietnam, I assume your water temps are very warm this time of year... perhaps 26-30 Celsius. You also state a pH of 7.8 and O2 of 8mg/l Ammonia presents itself in 3 different forms, according to the pH. At 7.8pH, ammonia presents as NH3-N, the most toxic form. Additionally, and unfortunately, the toxicity of NH3-N increases exponentially as the water temps rise above 20C. New, un-established bacteria are more susceptible to NH3-N toxicity than many fish... Thus, the system/s are in bio-overload from week #1. Mortality due to "N" cycle & NH3-N has several very common, visual signs. Due to burning from MH3-N, visual signs can be as minor fraying of some or one of the fins .. though to severe bleeding into the rays, skin, gills and eyes. Additionally - all external soft tissues, mucus membranes, eyes, gills and anus may show the same degree of visual variance, from mild burning to severe cellular bleeding. Also additionally - NH3-N mortality in established bio-systems presents slightly differently than it does in newly setup systems. In established aquaculture systems, NH3-N moralities effect a very high % of the total stock, it does so very rapidly... and all carcasses present with equal visual appearance. In new systems, the week and stressed get burnt - the healthier show resistance.... after a day or three has passed, those initial week burnt fish now have visual bleeding, burning swelling, fungus and bacterial issues... while those fish with initial resistance now begin to succumb and initial burning and bleeding begins. Thus within 5-10 days you can have a situation where moralities present in many different manners, and different stages of toxicity exposure... exactly like you photo. Some (most ?) fish appear to have very little visual signs (visually non-advanced), where as the main fish in picture shows every sign I have mentioned (visually highly advanced). So, what is a suggested avenue of mitigation ? 1. Water changes only reduce the concentration - not the toxicity. You need to lower the toxicity levels by lowering your pH closer to 7.0, and continue water changes. 2. As counter productive as it may sound, the addition of salt to the level of 2-3mg/l has huge benefits... far too many to add to this response. (search this forum) 3. STOP FEEDING THE FISH FOR 4 DAYS !!! Mortality during this period is 100% NOT due to starvation... it is 100% due to everything I have mentioned thus far. 4. Do Not Feed the Fish ! Correct - do not feed the fish until moralities stop. (especially for new systems) In an uncycled system, feeding your fish when the water is already toxic is equal to adding petrol to a fire. Sorry I didnt have more time to be more detailed in my response. Cheers Toga
  14. Happy New Year, Ande and everyone
  15. Hi 2savage Welcome to APN. Sounds like you are already on a great path. Ive some great childhood memories from the lakes area. I was born in Horseheads but moved to Oz in '75.... most of my older siblings went to Cornell Uni. Keep us informed on your progress mate & good luck. Cheers Toga
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