Aquaponics. Let's do this thing!

[Subrosa]

I use waste water from my rainwater tanks for orchids and that from my tapwater tanks to water tomatoes. The high calcium helps prevent blossom end rot. But it's not the only, or even the main source of N, P,& K. Leaf crops are probably the most suitable.

[rosemadder]

Originally Posted by Subrosa

The biomass of the fish needs to far exceed the biomass you intend to add to the plants through growth.

I think it's quite the other way around. An established aquaponics system can support more than 3x the volume of growing media than the volume of water in the system-- that will grow a lot more plants than fish.

From the numbers I've been reading, I've seen estimates of production running from 2kg to 7kg of veggie output per 1kg of fish output.

I have also read about one place where a student screwed up and had much lower than the intended fish load on the system, being fed 1/10th what they should have been-- and it was the first time that particular establishment had EVER seen nitrate deficiencies!

Originally Posted by catherinecarney

I agree on the laws of thermodynamics (and it wasn't directed at you--your comments are always reasoned--but there are a few who are quite hesitent to consider trying new things). The energy input, be it chemical/mechanical/solar/what have you must be greater than the desired output (entropy is always the fly in the ointment).

Granted, but...

The fish themselves produce approximately 1kg of protein per 1.5kg of feed (a phenomenal efficiency far surpassing that of land animals: it takes 8-10kg of feed to produce 1kg of beef). Even at the low end of veggie production, that's still far less fish food going in than plants coming out.

Van Helmont's willow tree gained 164lbs from somewhere-- and little did he know, it wasn't just the water. The dry mass of a plant is about 90% carbon and oxygen mostly pulled from the air, while other nutrients compose only 10%. Light is the silent partner here. Photosynthesis uses light as the fuel of a molecule-building machine, where fertilizer nutrients serve like specialized nuts and bolts amid the carbon and oxygen building blocks.

Sunlight is a phenomenal resource.

Originally Posted by catherinecarney

Corn is quite a heavy feeder compared to orchids or even other veggies, and it's probably one that won't be practical for hydro. Salad veggies, on the other hand, have proven reasonable, and I suspect that other "light feeding" crops may be as well.

Corn, you say?



Scanning their blog quickly, I think they're running a 400-gallon system with 35 tilapia, and this is only one of several grow beds.


Light feeding crops? Bah.

GROWING MASSIVE FRUIT TREES IN AQUAPONICS



OH YEAH.

Okay, I don't have the space for that kind of badassery, but... yeah. Don't discount the potential here.

Originally Posted by Subrosa

Given a typical home aquarium setup it's perfectly practical to grow and flower a few orchids or maybe produce a few strawberries with no other nutrient inputs. If however one wishes to grow even a small crop of corn the same way, the size of the aquarium required to do so given hobbyist stocking levels would be prohibitive in most houses.

Typical home aquarium setup, typical home aquarium setup... must talk self out of trying to grow a frikken mango tree in here-- ahem. Yes.

Home aquarium setup!
(not sure if these image links will work, gimme a moment...)





These are my plants. There are a few more outdoors. The Areca palm is still planted in potting soil, so it doesn't count, but everything else is in Hydroton.

All of my plants have been supported for one year by TWO FISH:


The Red Devil alone probably weighs.. hm, maybe a pound and a half? Include the pleco and they're probably 1 or 2 lbs of fish total. In a 30 gallon tank, that's still a bit lower than the 1lb/10gal stocking density that would still be considered a bit on the low side for aquaponics, but high enough to stress out the fish. A big part of why aquaponics systems are often larger, is that when you start measuring fish in pounds, you're using fish that grow large-- and a 1' fish really needs at least 100 gallons to even swim comfortably, even if he is alone. I've seen 1lb/5gal recommendations for hobbyist systems, while commercial systems go way way past that-- even up to 1/1, which is insane. At 1lb fish to 5-10gal water, you don't need anything crazy to keep them alive-- but it IS higher density than a total newbie would want to run out of the gate. In an ordinary kid's fish tank the recommendation is one INCH of fish per gallon of water, but that's to give max safety margin. To go higher, you absolutely must have a solid and established filter and a decent notion of what you're doing-- which isn't really hard.

But even with 1" of fish per gallon, you can totally grow some plants.

Originally Posted by catherinecarney

I'm also kicking around the idea of an attached greenhouse (attached to the east side of the house, eastern and southern exposure) with a superinsulated north wall, water collection from the downspout to feed into the growing area (and providing storage for thermal gain), a living roof (superior R value to conventional) and so on.

Awesome! Do it do it!

Originally Posted by Ray

There is a local grower of carnivorous plants and other wetlands species that has a very large tray filled with PrimeAgra, in which a variety of food crops are planted.

Water from a koi tank passes through a filter to remove solid matter, and the water is pumped into the plant tray. A standpipe maintains a minimum depth of reservoir, and the overflow goes right back into the tank.

Very cool. That's how I originally would have thought to do it as well, but from what I'm seeing a LOT of aquaponics systems actually use the growing media as the filter all in one-- worms and such break down the solid wastes, so they don't bother with mechanical filtration at all. Some let the pump suck the water directly out of the fish tank, pureeing the poo as it goes. I come from a koi background myself, where mechanical filtration is king, so that concept makes the hair on the back of my neck stand up!

I am very curious how it works for the carnivorous plants, with their much lower nutrient requirements-- probably the fish load needs to be lower so as not to overwhelm them?

Originally Posted by Orchid Whisperer

Do you intend to grow orchids this way? I think this might work with some vegetables or other plants, but I would be careful about keeping any orchid's roots too wet for too long.

Now, this is getting down to brass tacks.

Exactly how much exposure your roots get to the water in an aquaponic system depends entirely on your specific system setup. You can run aquaponics with deep water culture, roots fully immersed in water with no media at all. Or you can run a flood & drain system that periodically fills with water and then empties. Or drip irrigation. Or sub-surface constant flow. Or whatever. The list goes on.

I suspect many orchids would be able to adjust happily to a flood & drain setup.

Or, it would be pretty easy to set up an automated semi-hydro style system with sub-surface constant flow, where the water simply circulates through the bottom 2" of the media. The biofiltration and oxygenation capacity of such a system would be far inferior to the flood & drain setup, but it would work.

This is the stuff I'm pondering currently as I debate what I want to build myself.

[Subrosa]

Originally Posted by rosemadder

I think it's quite the other way around. An established aquaponics system can support more than 3x the volume of growing media than the volume of water in the system-- that will grow a lot more plants than fish.

From the numbers I've been reading, I've seen estimates of production running from 2kg to 7kg of veggie output per 1kg of fish output.

I have also read about one place where a student screwed up and had much lower than the intended fish load on the system, being fed 1/10th what they should have been-- and it was the first time that particular establishment had EVER seen nitrate deficiencies!

Granted, but...

The fish themselves produce approximately 1kg of protein per 1.5kg of feed (a phenomenal efficiency far surpassing that of land animals: it takes 8-10kg of feed to produce 1kg of beef). Even at the low end of veggie production, that's still far less fish food going in than plants coming out.

Van Helmont's willow tree gained 164lbs from somewhere-- and little did he know, it wasn't just the water. The dry mass of a plant is about 90% carbon and oxygen mostly pulled from the air, while other nutrients compose only 10%. Light is the silent partner here. Photosynthesis uses light as the fuel of a molecule-building machine, where fertilizer nutrients serve like specialized nuts and bolts amid the carbon and oxygen building blocks.

Sunlight is a phenomenal resource.


Corn, you say?



Scanning their blog quickly, I think they're running a 400-gallon system with 35 tilapia, and this is only one of several grow beds.


Light feeding crops? Bah.

GROWING MASSIVE FRUIT TREES IN AQUAPONICS



OH YEAH.

Okay, I don't have the space for that kind of badassery, but... yeah. Don't discount the potential here.


Typical home aquarium setup, typical home aquarium setup... must talk self out of trying to grow a frikken mango tree in here-- ahem. Yes.

Home aquarium setup!
(not sure if these image links will work, gimme a moment...)





These are my plants. There are a few more outdoors. The Areca palm is still planted in potting soil, so it doesn't count, but everything else is in Hydroton.

All of my plants have been supported for one year by TWO FISH:


The Red Devil alone probably weighs.. hm, maybe a pound and a half? Include the pleco and they're probably 1 or 2 lbs of fish total. In a 30 gallon tank, that's still a bit lower than the 1lb/10gal stocking density that would still be considered a bit on the low side for aquaponics, but high enough to stress out the fish. A big part of why aquaponics systems are often larger, is that when you start measuring fish in pounds, you're using fish that grow large-- and a 1' fish really needs at least 100 gallons to even swim comfortably, even if he is alone. I've seen 1lb/5gal recommendations for hobbyist systems, while commercial systems go way way past that-- even up to 1/1, which is insane. At 1lb fish to 5-10gal water, you don't need anything crazy to keep them alive-- but it IS higher density than a total newbie would want to run out of the gate. In an ordinary kid's fish tank the recommendation is one INCH of fish per gallon of water, but that's to give max safety margin. To go higher, you absolutely must have a solid and established filter and a decent notion of what you're doing-- which isn't really hard.

But even with 1" of fish per gallon, you can totally grow some plants.

Awesome! Do it do it!
Very cool. That's how I originally would have thought to do it as well, but from what I'm seeing a LOT of aquaponics systems actually use the growing media as the filter all in one-- worms and such break down the solid wastes, so they don't bother with mechanical filtration at all. Some let the pump suck the water directly out of the fish tank, pureeing the poo as it goes. I come from a koi background myself, where mechanical filtration is king, so that concept makes the hair on the back of my neck stand up!

I am very curious how it works for the carnivorous plants, with their much lower nutrient requirements-- probably the fish load needs to be lower so as not to overwhelm them?

Now, this is getting down to brass tacks.

Exactly how much exposure your roots get to the water in an aquaponic system depends entirely on your specific system setup. You can run aquaponics with deep water culture, roots fully immersed in water with no media at all. Or you can run a flood & drain system that periodically fills with water and then empties. Or drip irrigation. Or sub-surface constant flow. Or whatever. The list goes on.

I suspect many orchids would be able to adjust happily to a flood & drain setup.

Or, it would be pretty easy to set up an automated semi-hydro style system with sub-surface constant flow, where the water simply circulates through the bottom 2" of the media. The biofiltration and oxygenation capacity of such a system would be far inferior to the flood & drain setup, but it would work.

This is the stuff I'm pondering currently as I debate what I want to build myself.

You really think keeping a pound of fish in even 10 gal of water is easy and requires no special care? Try it for a few years and let me know how it turns out. As I said earlier it's all about expectations. Many folks put a Goldfish in a bowl and are proud that they kept it 10 years before it died, because of their initial expectation that Goldfish won't make it that long. Personally if I kept a Goldfish and it died before 30 years of age, I'd know that I probably failed it. Expectations. The examples you show are on a scale of size far greater that a typical home aquarium. If you scale the system up to planetary size, you could really grow some stuff!

[Ferns Daddy]

I've been using fish water for over 5 years on my Plumerias and they do very well with it.

[catherinecarney]

Cool info on this thread, and glad to see the things that people are coming up with.

I do hope to be able to do the attached greenhouse "someday," (you people are such bad influences) but need to hit the lottery first (grin).

Catherine

[rosemadder]

Originally Posted by Subrosa

The examples you show are on a scale of size far greater that a typical home aquarium. If you scale the system up to planetary size, you could really grow some stuff!

...Really? This seems THAT crazy to you?

The system with the corn in it is 400 gallons and looks like it has maybe 3 grow beds, with the corn planted only in one corner of one. You could conceivably grow a similar patch of corn with a much smaller tank-- if that corn is only taking up 1/4th of 1 grow bed, even if there are only 2 grow beds it's only using 1/8th of the system capacity, or around 50 gallons. I know people with 800+ gallon reef tanks at home. Maybe that's not "typical", but it's not as if aquaponics in general is some insane, ridiculous thing no one could possibly pull off at home. Stick some mint on a betta bowl, sheesh.

Did you at least get the part where I explained that the plant biomass exceeds that of the fish, and not vice versa?

Originally Posted by Subrosa

You really think keeping a pound of fish in even 10 gal of water is easy and requires no special care?

By "special", I was referring to the type of equipment that commercial systems use, such as oxygen injection-- not just air bubbles, pure oxygen-- pumps that generate a current for the fish because they have no room to properly swim otherwise, backup generators, etc. Hobbyist stocking rates don't require that sort of thing-- although backup power for surface agitation isn't a bad idea, especially in hot weather. As a side note, keeping 1lb of fish in 10lbs of water is all but impossible-- but 5lbs in 50gal much more plausible, or 20lbs in 200gal easier than that etc.

My roommate, with almost 0 knowledge of fishkeeping and minimal effort, has kept his Red Devil and pleco alive for several years in a tank far too small for them, using a filter I'd consider barely adequate for a 10-gallon system. That's 2lbs of fish in 30 gallons. Not quite 1/10, but getting there. Will these fish last for their maximum lifespan? No way. But improving their conditions would be very easy, if my roommate would just bother.

Originally Posted by Subrosa

Many folks put a Goldfish in a bowl and are proud that they kept it 10 years before it died, because of their initial expectation that Goldfish won't make it that long. Personally if I kept a Goldfish and it died before 30 years of age, I'd know that I probably failed it.

30 years is a long time for a goldfish, closer to the maximum end of their potential lifespan, even under ideal conditions. Many succumb to cancer, if nothing else. Even a lot of koi might not make it to 30, although some are rumored to be more than 100 years old.

In an aquaponic system, the grow beds themselves are part of the care for the fish-- and potentially superior to the forms of filtration that most household fish receive. In koi keeping, it's considered a good standard for your filter to have 1/3rd the total volume of your fish tank-- considerably more than that given in your average hang-on-back aquarium filter. In aquaponics it's 1/1, or even 2/1 and 3/1. And that's just the grow bed media alone, to say nothing of the plants. Most aquaponics systems are flood&drain systems, bringing extra air into the equation that can hugely increase filter efficiency. There is a LOT of filter power hooked up to an aquaponic system, and that in itself is a form of "special" care.

One of the primary issues with long-term pet fish care is nitrates. A lot of freshwater people don't even know nitrates exist, and a lot more don't worry about them because they're relatively "non-toxic" and won't kill the fish outright the way ammonia or nitrites will. Even those who know about nitrates, mainly control them with water changes-- which on their own can be stressful for the fish. Using a filter with plants brings nitrates under steady control. Of course, in aquaponic farming, the fish are often only grown out for one year or so, and then eaten for dinner. For ornamental fish, nitrate control can make a big difference for their life expectancy.

Anyway-- I'll say again, you can grow plants with 1" of fish per gallon. Maybe even less. Not sure exactly how many plants, but you can do it. My 50 gallon planted tank is stocked to that level, and the aquatic plants inside it grow so fast I have to trim them regularly.

It's actually a bit difficult to find much information on the difference in veggie output at the different stocking densities. Like I said earlier, in one place, it took a student accidentally feeding their fish 1/10th the amount they should have received, with fewer fish than he should have had in the first place, before anyone saw nitrate deficiencies.

Here's a breakdown of the range of stocking density levels:

Casual aquarium: 1" per gallon (note this is a very basic guideline that loses relevance fast with larger fish-- a single 10" fish far outweighs ten 1" fish). You don't necessarily need a filter, aeration, or water circulation at this level, if you're really good about regular water changes. Of course, even this is far higher than the levels found in nature.

Koi pond: 1 adult fish per 100-200 gallons. This takes a good filter, and a solid knowledge of what you're doing, but no extraordinary gymnastics. A mature full-size koi can weigh 20lbs or more, so the established fish/water ratio recommendation for koi keeping is actually not far off from the next one...

Aquaponics home farm: 1lb per 5-10gal This is for people actively trying to grow extra veggies and fish for their family, or even profitable small businesses.

Commercial fish farm: 1lb per 1-3gal These guys are raising fish to sell en masse. I don't even rightly understand why they feel the need to push the density that high, given the risks and stress on the animals, but there it is.


You can grow plants at ALL of those levels. The question is how hard you want to push for maximum output-- of FISH too, not just plants.

Anyhow. If anybody wants to look up more information on the specifics of aquaponics and how it works, Nate Storey's youtube channel is a great place to start:

Aquaponics & Vertical Farming Channel - YouTube

[Dart21]

Ray, which grower are you referring to? At Temple University-Ambler we have a whole Aquaponics setup and club that has been taking place and evolving over the last year and a half. They have gotten the basic systems down and experimented with quite a few different styles of aquaponics (float method vs drenched rubbermaid containers vs PVC NFT (Nutrient Film Technique) - these we have the most extensive work with at this point). I think the club would be happy to have anyone by to take a look. Though they aren't necessarily growing orchids, they are growing a wide variety of crops.

---------- Post added at 09:26 AM ---------- Previous post was at 09:20 AM ----------

Also the PrimeAgra obtained through Ray has proven to to leaps and bounds better than Hydroton IMO

[Ray]

Sorry, but they are dead set against visitors.

[Subrosa]

Originally Posted by rosemadder

...Really? This seems THAT crazy to you?

The system with the corn in it is 400 gallons and looks like it has maybe 3 grow beds, with the corn planted only in one corner of one. You could conceivably grow a similar patch of corn with a much smaller tank-- if that corn is only taking up 1/4th of 1 grow bed, even if there are only 2 grow beds it's only using 1/8th of the system capacity, or around 50 gallons. I know people with 800+ gallon reef tanks at home. Maybe that's not "typical", but it's not as if aquaponics in general is some insane, ridiculous thing no one could possibly pull off at home. Stick some mint on a betta bowl, sheesh.

Did you at least get the part where I explained that the plant biomass exceeds that of the fish, and not vice versa?

By "special", I was referring to the type of equipment that commercial systems use, such as oxygen injection-- not just air bubbles, pure oxygen-- pumps that generate a current for the fish because they have no room to properly swim otherwise, backup generators, etc. Hobbyist stocking rates don't require that sort of thing-- although backup power for surface agitation isn't a bad idea, especially in hot weather. As a side note, keeping 1lb of fish in 10lbs of water is all but impossible-- but 5lbs in 50gal much more plausible, or 20lbs in 200gal easier than that etc.

My roommate, with almost 0 knowledge of fishkeeping and minimal effort, has kept his Red Devil and pleco alive for several years in a tank far too small for them, using a filter I'd consider barely adequate for a 10-gallon system. That's 2lbs of fish in 30 gallons. Not quite 1/10, but getting there. Will these fish last for their maximum lifespan? No way. But improving their conditions would be very easy, if my roommate would just bother.

30 years is a long time for a goldfish, closer to the maximum end of their potential lifespan, even under ideal conditions. Many succumb to cancer, if nothing else. Even a lot of koi might not make it to 30, although some are rumored to be more than 100 years old.

In an aquaponic system, the grow beds themselves are part of the care for the fish-- and potentially superior to the forms of filtration that most household fish receive. In koi keeping, it's considered a good standard for your filter to have 1/3rd the total volume of your fish tank-- considerably more than that given in your average hang-on-back aquarium filter. In aquaponics it's 1/1, or even 2/1 and 3/1. And that's just the grow bed media alone, to say nothing of the plants. Most aquaponics systems are flood&drain systems, bringing extra air into the equation that can hugely increase filter efficiency. There is a LOT of filter power hooked up to an aquaponic system, and that in itself is a form of "special" care.

One of the primary issues with long-term pet fish care is nitrates. A lot of freshwater people don't even know nitrates exist, and a lot more don't worry about them because they're relatively "non-toxic" and won't kill the fish outright the way ammonia or nitrites will. Even those who know about nitrates, mainly control them with water changes-- which on their own can be stressful for the fish. Using a filter with plants brings nitrates under steady control. Of course, in aquaponic farming, the fish are often only grown out for one year or so, and then eaten for dinner. For ornamental fish, nitrate control can make a big difference for their life expectancy.

Anyway-- I'll say again, you can grow plants with 1" of fish per gallon. Maybe even less. Not sure exactly how many plants, but you can do it. My 50 gallon planted tank is stocked to that level, and the aquatic plants inside it grow so fast I have to trim them regularly.

It's actually a bit difficult to find much information on the difference in veggie output at the different stocking densities. Like I said earlier, in one place, it took a student accidentally feeding their fish 1/10th the amount they should have received, with fewer fish than he should have had in the first place, before anyone saw nitrate deficiencies.

Here's a breakdown of the range of stocking density levels:

Casual aquarium: 1" per gallon (note this is a very basic guideline that loses relevance fast with larger fish-- a single 10" fish far outweighs ten 1" fish). You don't necessarily need a filter, aeration, or water circulation at this level, if you're really good about regular water changes. Of course, even this is far higher than the levels found in nature.

Koi pond: 1 adult fish per 100-200 gallons. This takes a good filter, and a solid knowledge of what you're doing, but no extraordinary gymnastics. A mature full-size koi can weigh 20lbs or more, so the established fish/water ratio recommendation for koi keeping is actually not far off from the next one...

Aquaponics home farm: 1lb per 5-10gal This is for people actively trying to grow extra veggies and fish for their family, or even profitable small businesses.

Commercial fish farm: 1lb per 1-3gal These guys are raising fish to sell en masse. I don't even rightly understand why they feel the need to push the density that high, given the risks and stress on the animals, but there it is.


You can grow plants at ALL of those levels. The question is how hard you want to push for maximum output-- of FISH too, not just plants.

Anyhow. If anybody wants to look up more information on the specifics of aquaponics and how it works, Nate Storey's youtube channel is a great place to start:

Where to begin! I suppose a simple request that you calmly reread everything I've posted on this thread, and then point out exactly the things which I said that make you think that I think aquaponics, and combining it with aquaculture is crazy/doesn't work. Then you could take the time to read other things I've posted, and integrate that into the sum of your experience. Or you could just look at the pictures:

[Dart21]

Ah, Ray that's too bad. I hate places like that closed off to even students being educated thru a well known university and shutting the doors. Oh well, our doors at Temple U are always open to anyone with an interest in learning to further/broaden education instead of personal gain.