Guest post written by: Conor O’Higgins
Admit it: if you’ve been around the paleo community a while, you sometime dream about being in one of those idyllic hunter-gatherer-gardener societies of the past. The Inuit, Masai, Kuna, Hawai’ians – these traditional societies certainly had beautiful lifestyles and superior nutrition to modern industrial civilization. But my job is to dream of the idyllic hunter-gatherer-gardener society of the future.
There’ll be ten to fifteen billion of us on Earth soon, and it’s time to ask the Basic Practical Question: how are we gonna feed the tribe? Sachets of dehydrated astronaut food? Soylent Green? No thanks. What if I told you we can feed a growing population with high-quality organic vegetables, fish, meat, fruit and herbs, and do it all with less land, less labor and less water than we currently use?
There are a lot of smart people with a lot of smart answers to the Basic Practical Question: there’s permaculture, urban gardening, seawater-irrigated farming, aeroponics, open ocean farming. Today I want to talk about just one answer: aquaponics.
Raising fish in tanks – that’s aquaculture. Growing plants in enriched water – that’s hydroponics. Smoosh the two together and that’s aquaponics –you grow plants in water enriched by nutrients that are produced by fish grown in tanks. (By ‘nutrients’, of course, I mean ‘poop’.)
If you’ve ever kept a goldfish, you know that the tricky bit is keeping the water clean. The beauty of aquaponics is that the plants do this for you; as they extract the nutrients from the water, they clean it up for the fish. The result is a micro-ecosystem consisting of fish, vegetables, herbs… and a few paleo humans snatching up the surplus.
This system is as productive as it is elegant. Regular hydroponics can grow plants several times quicker than growing in soil. Aquaponics has this same advantage, with some research suggesting that aquaponics yields even more plants than conventional hydroponics (not even counting the fish).
Will Allen of Growing Power is successfully feeding 10,000 people on a three-acre aquaponic farm in downtown Milwaukee. The next time someone tells you it’s impossible to feed ten or twenty billion people sustainably, or that vegetarianism is the only way to do it, slap them with that example!
I believe that aquaponics and paleo fit together as elegantly as fish poop and plant roots. The paleo community meets the demand-end of aquaponics; paleo folk want a bunch of organic vegetables, fresh organic herbs, omega-3 rich fish, but no grains or beans?
If the paleo community is to make credible and comprehensive suggestions about the food we eat, then it needs to answer the Basic Practical Question. We need to suggest, and to demonstrate, how to grow food in the best, easiest, most efficient, and most sustainable way possible.
Back up. Did I say ‘organic’? Yep. An interesting thing about aquaponics is that it is organic by necessity. A big threat of chemical fertilizers and pesticides is that they’ll be transported by water to where fish live and kill the fish. Now if a farmer sprays these chemicals in open fields, the fish are miles away – and out of sight is out of mind. But when the entire ecosystem is contained in your basement, you better make damn sure to take good care of it and not poison one part of it to benefit another!
So what can you grow with aquaponics? Leafy greens like spinach are the staple produce of every backyard aquaponic bed, and aquaponists regularly churn out big lettuces and cabbages in 3-4 weeks. Kale is another aquaponic staple food that packs megadoses of vitamins and minerals, and has anticancer properties. But don’t think that aquaponics is limited to these – any herb or vegetable that can grow in a conventional garden will be happy in an aquaponic bed.
Tilapia is the most commonly used fish – it breeds like an aquatic rabbit and tolerates any kind of water quality. Jade perch grows nicely in aquaponics systems and has an exceptionally good omega-3:omega-6 ratio. In colder climates, trout and catfish can be grown. Carramundi, Murray cod and silver perch have also been used successfully. There’s an experiment I really wanna see someone try: prawns and tilapia together in the same tank. They like the same water conditions –and just think about the awesome ceviche you could make!
An interesting thing about aquaponics is its scalability. Aquaponics systems have been built in all sizes. Barrelponics is a system using 55-gallon drums, with the blueprints for building your own given freely to the world. There are other systems that cover acres and feed thousands of people. Interested in local food? Aquaponic systems can be slipped into basements, backyards and balconies everywhere, and many of the most interesting systems are in cities. Besides Growing Power in Milwaukee, there are too many other urban aquaponics heroes to count, like Eric Maundu who runs Kijani Grows in Oakland.
The paleo community need not feel guilty about the environmental consequences of the paleo diet. A healthy ecosystem consists of a varied network of plants and animals. It follows that if human communities are to take care of healthy ecosystems, we should grow and eat lots of plants and animals. A plant-only diet is not ecological. A grain-based civilization is not ecological. Only synergistic systems of plants and animals (including fish) are ecological. If we are to survive on this Spaceship Earth, we need to grow not crops, but ecosystems. We have all the know-how needed to create stable, organic ecosystems of plants, animals, insects, fish, fruit and fungi – and to nibble off bits of the ecosystem a few times a day!
So let’s build some ecosystems! If paleo is going to take over the world – and that’s the whole point right 😉 – we need to get busy growing sustainable ecosystems like aquaponics wherever there are people.
What do you think? Let me know in the comments.
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Conor’s mission is to feed the crew of Spaceship Earth. He has designed a permaculture farm in Guatemala, started an urban garden in Dublin, set up a gourmet mushroom cultivation project, and managed an aquaponics system in Haiti.
WOW…. we’re doing major backyard renovations right now — i wonder if i can talk my husband into an aquaponic unit instead of the koi-pond he’s planning? 😀
I really enjoy Conor’s posts.
I am looking forward to learning more.
Hey thanks!
I love the idea but every aquaponic system I’ve seen feeds fish other animal parts like waste chicken or fish. That is not sustainable. I hope someone is working on a system that only needs sun and water to thrive :).
Right. Some people say that aquaponics is a closed-loop system, but that’s not entirely true because what do the fish eat?
Honestly, most systems I’ve seen just use store-bought processed fish food. There are a few sustainable solutions, though:
– Some algae will grow in the tank, especially if you throw in some junk with a high surface area. However, in real life, you won’t grow enough algae to meet more than a small part of the fish’s diet – that’s just arithmetic.
– Black Soldier fly larvae are one thing I’ve worked with. You can turn kitchen scraps into highly nutritious grubs that will crawl right into the fish tank for you. http://blacksoldierflyblog.com/biopod-log-waste-in-grubs-out/
– Duckweed can grow on sun and water, as you say. I believe it is the fastest growing plant in the world. A barrel cultivating duckweed next to your fish tank is a good idea. http://www.mobot.org/jwcross/duckweed/duckweed.htm
– I saw one system with a little LED light an inch underwater. This attracted insects at night, and the fish gobbled them up.
The LED light is a neat idea. I think one time I heard someone mention something about using some sort of bug zapper above the fish tank to give a good supply of insects for the fish to eat.
Unfortunately, “bug zappers” kill a lot of beneficial insects, and I don’t like to use them because of that.
Sounds interesting. There’s lots of discussion in ancestral health circles about soil health and fertility for driving more productivity and more nutrient-dense crops.
How does hydroponics / aquaponics square with this? Love to see some nutrient density comparisons of the same type of spinach grown in hydroponics vs. aquaponics vs. conventional vs. organic vs. “beyond organic” …
Mike, I absolutely agree with the need for some research to compare the nutrient-density of food grown in different ways. We don’t want just high yields per area. We want food with the highest density of nutrients possible, that is still grown in a practical and ecological manner.
I think it would be a great idea to put together a research project to compare the effect that different agricultural/gardening methods have on nutrient-density. Probably the best way to financially support this research would be to use crowdsourced funding. I wonder if the Paleo community would be interested in supporting this?
“we need to grow not crops, but ecosystems”! Fabulous. I like that sound bite. I have been working on plans for some permaculture water systems here on our property…. This concept definitely needs to get worked in.
Sounds great. Why doens’t this ruin the fat profile the way “farm raised” does? are the fish eating the vegetation?
Kyle: it depends what you feed the fish. If you feed them the grain- and soy-based stuff most fish farms do, then yeah, you’ll end up with a worse fat profile than wild fish. See my comment above about different options for fish; my ideal would be to feed them something similar to what they evolved to eat in the wild.
Great post! I have seen a polluted stream in India “cleaned” by a succession of screens, plants, fish. Water goes in dirty, flows through a gorgeous park (your land?), and comes out clean. If one had property with a stream, doing this with edible plants and fish that have plenty of meat on their bones, what a terrific food source. Think of the possibilities!
Hey Connor.
You might be interested in what an aquaponics sorta outfit in Watsonville is up to. They’re featured in a newly launched crowdsource funding platform called “Barnraiser”. Check em out here: http://www.barnraiser.us/people/jon-parr
-Joe
Conor, while aquaponics has a lot to offer, it’s very deceptive to claim that we can feed 10-20 billion people this way because “Growing Power” can feed 10,000 from a 3-acre aquaponics farm.
Nearly all aquaponic farms import a large amount of feed for their fish, usually composed of grain and fish meal. It takes a whole lot more than 3 acres to feed enough fish for 10,000 people. While, as you mentioned, there are some possible alternative food sources for the fish, it remains to be seen if those sources can reliably supply enough to feed a significant number of fish. I hope more research is being done on these options.
In addition, while aquaponics can be considered an “ecosystem”, it is a man-made system that requires a tightly controlled enclosed environment with constant energy and feed inputs. Can that be considered sustainable if used planet-wide? How does the sustainability of that type of system compare with grazing animals on pasture, and rotating some pastures with growing organic vegetables every few years?
I’m not trying to be argumentative. Aquaponics definitely offers good benefits in some situations. I just don’t think any one system or method of growing food can be considered a panacea for our world food crisis.
As for sustainability issues, some people even believe that bringing in ground rock fertilizers for backyard gardens is unsustainable. No system will be perfect. However, I agree that vegetarianism may be one of the least sustainable diet options – in terms of soil destruction and required energy inputs.
Thanks for your input, Debra.
To answer your question, yes, I do believe that a man-made, controlled, enclosed system can be considered sustainable. Why not?
‘Unsustainable’, as far as I understand, means that a system has negative side-effects that eventually cause it to break. (Soil depletion is a fine example.) Aquaponics is an artificial system requiring a small input of electricity, pumps, and maybe some sensors – none of these things cause significant damage.
I think people sometimes get confused between ‘natural’ and ‘sustainable’. Aquaponics, I think, is unnatural, sustainable, and very productive.
Certainly aquaponics is not a panacea; I have articles on this site about other methods of food-produxion too:
http://robbwolf.com/2013/10/09/permaculture/
http://robbwolf.com/2014/04/24/grass-fed/
What a dream to go back to the “idyllic hunter-gatherer-gardener”. It’ll be so good for us <3
In France, we've just discovered the aquaponics… 10 or 20 years later than english countries…