Rosso Carne

ITT we discuss Decoupled / Open loop / Multi-circuit aquaponics systems

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So what about the water budget when moving solids from RAS to plant loop?

How much water needs to be moved from fish loop to maintain healthy levels of nitrogen for fish?

And how much water can you actually move to plant loop without flooding the plant side?

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So what about the water budget when moving solids from RAS to plant loop?

How much water needs to be moved from fish loop to maintain healthy levels of nitrogen for fish?

And how much water can you actually move to plant loop without flooding the plant side?

 

How long is a piece of string.. :D

 

The water budget/requirement will depend on the number of plants.. you location, temps, humidity etc... :D

 

As a "generic" guide.. I'd suggest that your water budget would be at least equivalent to the amount of water your plants require... and any losses through transpiration etc..  :D

 

And why does all that water budget have to come, or go...to and from the RAS loop?... aren't you "decoupled"... ;)

Edited by RupertofOZ (see edit history)
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Lol.. I guess it doesn't have to come from the plant loop. But you still like to maintain healthy nitrogen levels for the fish.. once you do the math on that you get a certain amount of water change..

So surely you want to move all that precious nitrogen too your plants. ;)

Once all that water is in the plant loop it needs to be able to handle the volume of water. Generally 5-10% of fish loop volume is being changed in a normal RAS.

Sure all the things you mentioned like evapo-transpiration etc.. Will determine the water loss in plant loop..

So what levels of nitrogen do you find to be ok for tilapia or trout in your case Mr Oz?

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Tilapia are a banned species in Australia...

 

There's some recent conjecture regarding "safe" levels of nitrates.. and juvenile "fry" of trout are more suseptible to prolonged elevated levels...  suggested around 150 ppm...

 

Previous lowest levels reported for normal grow out... were about 450 ppm... for bluegill... but as I said there's some more recent conjecture that optimum limits should be lower.....

 

And I try to use ALL my nitrogen.. to grow plants... not fish... anyway...  :D  :D

Edited by RupertofOZ (see edit history)
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I guess you can figure out your sq mt of growing area, figure out your feed ratio for that area then that would tell you how many kg of fish you need to eat that food, calculate your stocking density and that can give you a rough idea of the size of your ras system needed. What we don't know is how quickly the plants will use the nutrients which means we don't know how often fish water needs to be replenished to the plant loop. I guess just replenish as the plant loop sump starts to get low...

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 I guess just replenish as the plant loop sump starts to get low...

 

Top it up.. and suck it and see... fair enough backyard approach...

 

Seems to have found a place within the commercial aquaponics circle as well... :D

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Wouldn't you want to start by deciding how many fish you would like to grow?

If we start there and Then size the plant section accordingly to use those nutrients. Then we have figure how much water in plant loop that is lost. If that happens to be less than what you bring over from fish loop I guess we are going to need a really large holding tank. :)

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Wouldn't you want to start by deciding how many fish you would like to grow?

If we start there and Then size the plant section accordingly to use those nutrients. Then we have figure how much water in plant loop that is lost. If that happens to be less than what you bring over from fish loop I guess we are going to need a really large holding tank. :)

Same same but different

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Think about it. ;)

Thanks for the clarification in ccontext of volume although think we're talking to different types of sludges.

Anaerobic digestates involve undecomposed lignins and cellulose, which becomes decomposed aerobically. Aerobic's activated sludge is a biofloc of living organisms, which then obviously needs dewatering.

I imagine large city treatment plants involve anaerobic processes due to more than just human and animal wastes are involved, which this "other industrial" waste is likely better decomposed.

Edited by crsublette (see edit history)

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Adding worm castings to an aerobic digester is nothing like the activated sludge process.  

 

Activated sludge is about continuous recirculating a portion of the old feedstock in the with new feedstock - to accelerate the proliferation of oxidising bacteria.

 

Gary

Yep, I understand that... but... as it is done to "accelerate the proliferation of oxidizing bacteria" to decompose the waste... Would adding worm casting also "accelerate the proliferation of microorganisms" so to increase waste decomposition? Much like is the purpose of compost teas... so to grow organisms so to increase decomposition to make nutrients more plant available...

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Hi TF,

 

You can call yourself Tropical Farmer (or anything else you want) and you'll be welcome here.  I looked at the blue system you and your dad built - very nice indeed.

 

Looking forward to hearing more from you.

 

Gary

 

thank you Gary. I chose the same name I use on the other forum as it's lots of usual suspects on these forums and this way people can at least see my history. The global AP community is pretty small.

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Top it up.. and suck it and see... fair enough backyard approach...

 

Seems to have found a place within the commercial aquaponics circle as well... :D

 

It may not be popular here but to me this is a good reason to attend Chatterson's seminar if geographically/economically viable. He's got over a year's worth of data to share pertaining to this configuration and that's something hard to find. I don't think anyone can argue his results. He claims his system is zero waste so either his plants are sucking up the water at the correct rate for the fish water replenishment or he's returning water to the RAS system. It's one thing to have the basic idea of the setup but all the important details come with time and experience. Learning from someone like him or Paul can save you a few years of tinkering but I have no doubt additional tinkering will always be needed.

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Sorry, but I think the incorporation of an anaerobic tank... in a mineralisation loop.... is just pure nonsense... especially as a first stage....  or any other stage for that matter... unless offline (in it's own decoupled loop :D )

 

And properly sealed so that the volatile gaseous ammonia does not exit from the surface...

 

Don't know why there is a fascination with anaerobic digestion... I guess, so to remain "holistic", then anaerobic digestion "just has to be involved"... But what I think folk do not release... anaerobic digestion occurs in nature due to limited mechanisms of its environment... such as our stomachs or a lake bottom... a healthy person, or lake, has zero choices as to how our food or waste gets digested.... simply is what it is... except not "how it is" for us since, in our hands, control of environmental mechanisms is quite dynamic.

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What we don't know is how quickly the plants will use the nutrients which means we don't know how often fish water needs to be replenished to the plant loop. I guess just replenish as the plant loop sump starts to get low...

 

Just gotta realize that there will always be a variance... and there will likely always be some level of excess water, which you can easily use by sending to a closed wicking bed or use it to irrigate your fruit trees...

 

Don't think any grow method has shown to grow trees well... so... just send the excess water to the nut or fruit trees... or to a flower garden with particular plants that attract beneficial bugs or repelling the bad bugs. :)

 

 

He claims his system is zero waste so either his plants are sucking up the water at the correct rate for the fish water replenishment or he's returning water to the RAS system.

 

Or... he has a plan for the excess water, rather than return to RAS, so that there is zero waste. ;)

 

 

Learning from someone like him or Paul can save you a few years of tinkering but I have no doubt additional tinkering will always be needed.

 

Yep, this is so true... Unfortunately... "Learning" can be boring and folk just want to get their hands dirty... So, if this involves alot of unnecessary screw ups and a treasure chest of expensive PVC pieces, then its still all good since it went to a good cause, except much of it could have been bypassed if they just wanted to school them self first, from folk like Mr. Van der Werf and Mr. Chatterson, before getting their hands dirty...

 

Ultimately comes down as to how well you know the variables involved... X fish food will equate to Y nitrogen and Z other nutrients. Look at some agronomist data for plant nutrient and water consumption as a baseline benchmark. Try to do a mass balance equation... As time goes on, more information from others will be learned about particular constants, so then the balance equation can be further adjusted.

 

So... this way... you will know if you have too few or too many fish... too few or too many plants...

 

I don't know of any system where these type of calculation do not apply.... This should be taught to beginners at the same level as Nitrification is taught to them... It is all very important...

 

 

One of the most common beginner mistakes I have seen in the goldfish watergardener hobby... Too many fish (or feed too much) with too few plants or too little filtration in too small of a system.

Edited by crsublette (see edit history)

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I'd be curious on what it'd be for Trout since I am always told Trout requires more clean water since they are a "river" type fish. Bah, forget tilapia... Tilapia just reminds me of an ugly goldfish ;) Trout is what I am aiming to raise... Even if I have to use a chiller for the fish tank water, i'm still going to do it...

 

I love Trout... As a kid, I would go out camping and all we would eat for 3~4 days was just Trout... with maybe an MRE once a day... Trout is crazy easy to clean, no deboning nor descaling required, easy to cook... Heck, I started out when I was 5 years old catching, cleaning, and cooking my own Trout... and Trout has an awesome flavor...

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I'd be curious on what it'd be for Trout since I am always told Trout requires more clean water since they are a "river" type fish. Bah, forget tilapia... Tilapia just reminds me of an ugly goldfish ;) Trout is what I am aiming to raise... Even if I have to use a chiller for the fish tank water, i'm still going to do it...

 

I love Trout... As a kid, I would go out camping and all we would eat for 3~4 days was just Trout... with maybe an MRE once a day... Trout is crazy easy to clean, no deboning nor descaling required, easy to cook... Heck, I started out when I was 5 years old catching, cleaning, and cooking my own Trout... and Trout has an awesome flavor...

 

 

I'd have to agree with you on the taste of Rainbow trout or steelhead trout, assuming that is what you mean.  Here in Louisiana we have a speckled trout that is not related to the salmonid types of fish at all.  It's good, but it doesn't come close to the flavor.  Growing up in Louisiana, I have easy access to fish, but I find it ironic that my favorite is a kind of fish that doesn't grow natively when we have all of this food readily available..

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