An interesting idea for farming

I was reading an article recently about a farmer here in Arizona that came up with a great idea.  Basically, he figured since he was having to pump water out of the ground to water his crops anyway, why not temporarily hold the water in a pond and grow some Tilapia in it?  The cost of feeding the fish is offset to some extent by reducing or eliminating the need to fertilize the crops.  By constantly cycling fresh water through the pond you don't have to worry so much about water quality.

This seems like such a great idea, I wonder why more farmers aren't doing it, or perhaps they are and I just haven't heard about it before.

http://www.westernfarmpress.com/management/growing-fish-arizona-desert

Hi Peter. I think the reason that it isn't more widespread is this whole specialisation bent we're all on as a society. If you're operating a land-based fish farm, you're not thinking about other operations because it's taking all of your time already. It will enter your awareness if you have a problem with your "waste product," and so if reuse of the effluent is easier and cheaper, or even better, helps to offset your feed costs, even better. But the fish farming aspect is still top of the pile in terms of priorities.

Having said that, I think that it's an easier path for a fish farmer to make than a conventional ag farmer.

I think some of the specific issues of integrating aquaculture with agriculture, as opposed to just dumping your effluent as fertiliser on bonus crops, is that the amount of effluent produced by fish is way more than necessary for a farm on the same scale. So yes, this can be a boon, where a small family is keeping fish ponds that feed them ably, and produce enough fertiliser not only for their kitchen garden and their own food crops, but for the market portion of it as well.

It's a great idea. I want to use it myself, possibly with an aquacultural setup involving salmon, but I would settle for trout.

-CK

What about an aquaponics system instead. It's cheap to build, you don't need to use fertilizers once the system is balanced (usually it takes few months), water is cleaned and filtrated by plants and the water remains in a (more or less) closed loop. This way you don't consume too much water and yet, farm as long as you want.

Hi Jennifer.

I do apologise, but I believe you have it backwards. Aquaculture is the term for systems that can function in a closed loop, where biological actors (plants and animals) are performing all the necessary functions of an aquatic system. Aquaponics refers to the less-sustainable version, where you're running a relatively conventional hydroponic system, but using the dirty fish water as your nutrient solution.

-CK

Peter VanDerWal wrote: This seems like such a great idea, I wonder why more farmers aren't doing it, or perhaps they are and I just haven't heard about it before.  

Paraphrasing Joel Salatin's impression of the average farmer being introduced to permaculturey ideas: "I'm already working 80 hours a week and now you want me to work even more?"

I'd say that lines up with what I see around here, the older generation of farmers would take less work over developing new projects for extra money. I can pitch a simpler permaculture idea that requires a week of work over the summer and gets no interest, but if I talk about how their land has gravel under it, they are very interested to stop working a piece of land while getting some supplement income.

The fish idea is good though and I'm sure many newer generation farmers with small farms will try it out.

I was thinking the same thing, they would most likely have to hire more folks to make it work, and it would be a different skill set.  You'd probably want multiple ponds so you didn't have to process all the fish at the same time.  You'd need someone to manage feeding them, for maximum profit the amount you feed has to change almost daily.  If you had a large operation you'd probably want lots of separate ponds, which means you either lose some arable land or end up tucking the ponds away in various locations where it's not useful to grow crops, and that makes management more time consuming.
Also, if your operation is large enough, you'd want to breed your own fish(more work), and means you'd want to grade them for growth when they are a few weeks old (more work) .

For a one man shop this isn't likely to work out, although maybe if you took on a second worker....  However, these days most produce comes from large farms run by corporations, for them as long as they can make a profit off of it they will generally be open to the idea, even if they have to hire on more people.

Jennifer Parker wrote:What about an aquaponics system instead. It's cheap to build, you don't need to use fertilizers once the system is balanced (usually it takes few months), water is cleaned and filtrated by plants and the water remains in a (more or less) closed loop. This way you don't consume too much water and yet, farm as long as you want.

It is extremely difficult to make large scale aquaponics profitable, in fact the majority of commercial aquaponics companies make more money off the side streams (teaching, selling supplies, etc.) than they do off the fish and produce, that is among those companies that actually make a profit.
http://www.sciencedirect.com/science/article/pii/S0044848614004724

An Australian example http://www.abc.net.au/news/rural/2017-02-08/farming-murray-cod-on-murrumbidgee-irrigation-area/8250490

I have been thinking about a similar idea. I live at the base of a mountain, so there are all kinds of glacier ponds above me and a very large pond/swamp behind me and just heading into our property, then making a bit of a stream along the property line. the stream is stagnate and so the land around it is very Quishy, On the plan I used for my PDC I designed a pond taking the water out of that stagnate stream filling the pond and using swales to bring that water over to the plantings.  Along the sides of the pond and swales We would plant cranberries, blueberries etc.  There are other streams that lead off of the huge pond/swamp that eventually lead to an important lake (it was on the New Hampshire coin in 2013) which is just a mile from us. So I know that if we gave this stream somewhere to go it should clean up. Right now you can't get there without wearing waterproof boots and prepare to get wet, walking through the quishy/boggy area around it. The cleaner streams & brooks have a good supply of trout or Brookies and the smaller ones are called, so gathering up a few trout would be hard to do.

There used to be a system in France similar to this . A field would be turned into a pond as soon as the wheat was harvested some carp introduced left for 18 months ,drain ,fish and frogs ( well this is France :-) ) harvest the big enough fish put the small ones in a new pond , plant wheat .

Chris Kott wrote:Hi Jennifer.

I do apologise, but I believe you have it backwards. Aquaculture is the term for systems that can function in a closed loop, where biological actors (plants and animals) are performing all the necessary functions of an aquatic system. Aquaponics refers to the less-sustainable version, where you're running a relatively conventional hydroponic system, but using the dirty fish water as your nutrient solution.

-CK

Aquaculture is the term for fish farming.  Aquaponics is the term used for combined aquaculture and hydroponics -- fish farming combined with growing plants in a water medium.  

Kathleen

ETA:  The idea of using a pond with fish in it to water a vegetable garden is a good one; it doesn't sound like it would be closed-loop like aquaponics basically is.  You would need to be able to replenish the water level in the pond, which would have a greater water loss than an aquaponics set-up.  But you would have the advantage of being able to grow your plants in the ground (which I suspect probably leads to higher nutritional levels in the food grown), and also it would probably be easier to keep the fish water in balance.

Yeah, I have heard the terms used differently, the "culture" part of aquaculture being used to refer to the self-sustaining nature of the system designed. So instead of piping and reservoirs and pumps, you try to use natural elements where possible. While you might still need to add oxygen mechanically, because few of us will have the opportunity to make use of a natural waterfall, your gardens would be planted in chinampas, you would have as much aquatic vegetation as could be supported, duckweed would probably be harvested for livestock, their manure  would enrich the surrounding system, which would provide some additional feed for the aquatic denizens, and the cycle continues.

Contrast this with aquaponics, basically a fish tank whose filter is your garden bed, except your plants aren't necessarily in soil. And everything is dependant on human intervention and technology, neither of which is as reliable as a properly designed biomimetic system.

-CK

Please consider the vast amount of evaporation you will get from the pond surface.  Might be a deal breaker in Arizona...

Rice-Fish farming is practiced in Asia - in countries such as the Philippines, Indonesia & Bangladesh -- and it provides a valuable source of protein. Fish fingerlings are introduced to the paddy at the beginning of the season and grow large enough for useful harvest when it's time to drain the field. A number of different species are used, among the tilapia, carp and catfish. apparently 5000 tilapia fingerlings per hectare ( = 2.47 acres) can yield 100 to 200 kg of fish in a 70 - 100 day growing season. That translates to 89 to 178 lbs per acre.

This is the normal way of doing things in Asia, but sometimes a well is unnecessary if catching enough rain.

Woozie Wikfors wrote:Please consider the vast amount of evaporation you will get from the pond surface.  Might be a deal breaker in Arizona...

There is a formula that calculates evaporation and gives you the right depth. 4 meters seems to be the most common

I know it is considerably warmer in Arizona than where I am (where the Alaska Highway starts).  I don't know how windy it is, but hot and windy is not a good combination for ponds.  I have wind here.

There seems to be lots of rock in Arizona.  If the rock contains reasonable calcium (limestone does), there might be another thing to fit in this cascade.  In my part of the world, one of the more ideal places would be an old gravel pit, as the aggregate typically had a reasonable amount of calcium in it.

But taking the runoff from a fish tank, and putting it into another "tank" with crayfish/crawfish might be useful.  They are scavengers, and would gladly eat dead fish.  And lots of other dead things.

Up here, for the cold water crayfish I was looking at, I ran across just how good these animals are at "jail escapes".  I would say they are the goats of the crustacean world.  Apparently in grassy places, they will walk up to 4 miles on grass at night (when the night has a lot of dew) to get from where they are (jail) to someplace else.

Louisiana has lots of crawfish places, and probably the same would work in Arizona?

The exoskeleton of them, would probably be called chitin in Japan.  There is a processed version called chitosan.  These are both useful starting materials for a variety of processes.

But you would need to investigate their ability to go walk-about on you.  It probably means tall vertical walls on their tanks, far beyond what you need to contain the water.

Chris Kott wrote:Hi Jennifer.

I do apologise, but I believe you have it backwards. Aquaculture is the term for systems that can function in a closed loop, where biological actors (plants and animals) are performing all the necessary functions of an aquatic system. Aquaponics refers to the less-sustainable version, where you're running a relatively conventional hydroponic system, but using the dirty fish water as your nutrient solution.

-CK

I own a small aquaponics system at home, that is almost 100% self-sustainable. I use few solar panels and a battery for the pump. Water evaporation is very small compared to any other system. The plants and fish do all the work. Why is this a less-sustainable version?

Peter VanDerWal wrote:

Jennifer Parker wrote:What about an aquaponics system instead. It's cheap to build, you don't need to use fertilizers once the system is balanced (usually it takes few months), water is cleaned and filtrated by plants and the water remains in a (more or less) closed loop. This way you don't consume too much water and yet, farm as long as you want.

It is extremely difficult to make large scale aquaponics profitable, in fact the majority of commercial aquaponics companies make more money off the side streams (teaching, selling supplies, etc.) than they do off the fish and produce, that is among those companies that actually make a profit.
http://www.sciencedirect.com/science/article/pii/S0044848614004724

Thanks for the link. I will read the study as well. I don't really have experience with large-scale systems...but I don't get why they wouldn't be profitable.

Hi Jennifer.

The reason the system you describe is less sustainable in my opinion is because it relies on solar panels and pumps.

This isn't intended as criticism, just to explain what I understand as the difference between the two terms in a specifically permacultural context, where one of the key ideas is that the most sustainable systems are self-sustaining, without human intervention.

Yes, panels and pumps and everything else will last for a while, perhaps paying their costs off several times over a lifetime. But keeping them running requires either human effort or more complex controls. The more contrived the infrastructure necessary to support a system, the more potential for something to go wrong.

Which is definitely not to cast judgement on aquaponics, just to point out some strengths of systems that are closer to natural ones, designed to operate without humans once established.

-CK

Here is a farm raising shrimp in AZ. Desert Sweet Shrimp

I've also watched videos of people doing small scale lobster farming.  I would guess that requires cool water, though.  You can find them on Youtube.  It's fascinating.

Chris Kott wrote:Hi Jennifer.

The reason the system you describe is less sustainable in my opinion is because it relies on solar panels and pumps.

This isn't intended as criticism, just to explain what I understand as the difference between the two terms in a specifically permacultural context, where one of the key ideas is that the most sustainable systems are self-sustaining, without human intervention.

Yes, panels and pumps and everything else will last for a while, perhaps paying their costs off several times over a lifetime. But keeping them running requires either human effort or more complex controls. The more contrived the infrastructure necessary to support a system, the more potential for something to go wrong.

Which is definitely not to cast judgement on aquaponics, just to point out some strengths of systems that are closer to natural ones, designed to operate without humans once established.

-CK

Now I understand your point. Sorry, I understood it wrong first time :)