Aquaponics in a Nutshell

Tilapia enjoying a nice morning swim My new life as an urban farmer is off to an excellent start.  I am making friends and, everywhere I look in Chicago, there are Windy City Harvest graduates doing excellent things to improve the food system.  I am on a good track to make the difference I feel compelled to make.

When I tell people about my program, I usually mention the aquaponics system at WCH, because it is a bit of a buzzword, especially as marijuana becomes gradually more legal around the country.*  You can absolutely use aquaponics to grow pot, but that's not really why it was designed.  We had a lecture on aquaponics today, and it was incredibly illuminating, and I'm not just talking about grow lights (haha!).

The guy who designed and runs the aquaponic system at WCH is a very knowledgeable individual named Andy.  We are not formally trained in aquaponics as part of our certificate program, but he said that the same science behind horticulture follows through to aquaponics and he's totally willing to teach people the basics one-on-one as time allows.  So, I only know what Andy was able to squeeze into a 1.5 hour lecture, but I will do my best to regurgitate the main points below.

First, where does the word "aquaponics" come from?  Well, there was hydroponics, the growing of plants in nutrient solution without soil, and there was aquaculture, the raising of fish in pools for the sake of food.  Both of these systems of food production, while innovative and interesting to think about, are immensely wasteful.  Hydroponics doesn't really have a good solution for what to do with plant waste water, it's very costly to set up, and the systems are very susceptible to mold issues. Aquaculture is a big polluter; you are essentially setting up a cattle feed lot for fish. Aquaponics, however, uses the waste nutrients from the plants to nourish the fish, and the waste from the fish to feed the plants. The crucible for development in aquaponics was the Virgin Islands in the 1970's.  It is really something we can thank the hippies for.

It is a bit more complicated than that, and you do have to feed the fish, but the cycle is way more sustainable than keeping the two separate.  The water that starts in the system stays in the system.  The only waste is a little solid waste from the fish, but there are ways around that as well.  Thus, the number one advantage to an aquaponic system is water conservation.  In addition, you don't need soil, you minimize pollutants going into the ground water, and the systems are incredibly adaptable and scale-able. Andy gave us an example of a home sized system, with a 10 gallon tank for a couple fish and a plastic tub on top for the plants.  You could have fresh basil, mint, bok choy, and some types of lettuce year round with this type of set up.  The initial set-up cost would be around $50 and that would pay for itself in a winter or two.

Individual home-sized aquaponic set-up

There are challenges to this type of system, as there are with anything.  It takes a bit of an engineering mind to build out a system to begin with, and evidently sometimes you don't know if you are doing something wrong until basically the whole system fails.  I mean, pretty much any science/trade/field has critical points of failure, but in this case, you could lose a lot of time and money if the system you put together has a critical flaw.

Once your system is set up, you become the grandmaster of tedious balance of pH and nutrients.  Andy showed us a really lovely chart that lists the 10 most essential nutrients for plants and the pH at which they are most available to the plants in solution.  It is in the slightly left of neutral range of 6.5 to 7 pH.  Any more acidic and things start to die.  I didn't take great notes on the actual processes and chemical conversions that are going on, but the basic cycle is as follows: feed fish, fish exhale ammonia through gills, ammonia is consumed by nitrosomous bacteria which turn it into nitrites, which nitrobacter bacteria eat and turn into nitrates which are the lovely nitrogen rich compounds that make plants super happy. Most systems do produce some waste at this point, which can be composted. However, at WCH they have an intermediary bed system, which has different plants in coconut coir for aeration, sitting in puffed shale that has red composting worms living in it. The worms feast on the extra bacteria and waste from the fish, so the system itself has basically no solid waste.  The other boon to this approach is these shale composing beds can support more intense root systems. So you can grow tomatoes, hot peppers, peas, and so on, making the whole system more profitable and/or delicious, depending on your perspective.

So, basically, that's aquaponics in a nutshell.  If you have a flair for tinkering with pipes and fish and plants, it might be a good hobby for you.  Some folks who do aquaponics grow enough fish to sell them to processing companies, but it's mostly tilapia, and the vast majority of tilapia are being grown way more cheaply in other countries in polluted waters. Andy says that WCH is planning on moving from tilapia to koi, mostly because they don't grow enough fish to keep a regular distributor.  Koi can be sold for way more money as ornamental fish once they outgrow our aquaponics system.

See more pictures below and let me know if you have other questions about aquaponics.  I'm soon to learn all about soil science, so I will have a better idea of what specific types of plants need in their soil at an elemental level.  Exciting stuff!

Basil growing in the floating beds

Cucumbers growing in the media beds, fed by the worms

Sump and pump directly below the media beds

* I honestly know nothing about marijuana, having never touched the stuff, but you do you, friends!

Sustainably Queer Urban Agriculture: A New Chapter for Rachel

Image We are still doing our best to get back to a regular posting schedule, but sometimes life happens and it's very unpredictable  At the moment, no one is really banging down our door asking for MORE POSTS IMMEDIATELY (although we could probably use some additional external motivation), but we honestly do have a list of possible posts about a yard long.

We're not trying to make excuses over here, but part of the reason our whole life is in flux is that I (Rachel) have recently started an intensive 9-month program in Sustainable Urban Agriculture! It is a program called Windy City Harvest, put on through a partnership between the Chicago Botanic Garden and Daley College of the Chicago City Colleges. The classes themselves take place (for the most part) at the Arturo Velazquez Institute, a.k.a. the West Side Technical Institute. This is the program's 7th year in existence and I am more than thrilled to be a part of it. (A lot of the exciting ventures focusing on local food in Chicago were started by or employ WCH graduates, and the recently opened Eataly enterprise hired 6 graduates at the end of last year!)

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The 9-month program starts with a spring semester with intensive classroom work (learning about stuff like greenhouse propagation, botany, soil science, and systemic environmental issues) and actual farming work in the AVI greenhouse and Rodeo farm near campus. The WCH staff runs 6-7 different farm sites in the city, and part of our job as students is to prepare seedlings for those farms and assist in transplanting. All this is to say, I've already been actively involved in prepping a farm for the growing season, and it is VERY HANDS ON. (Who knew soil blocking would be so labor intensive?!! Who knows what soil blocking is besides other farmer-y types and Kristl who has been helping me study?!)

We finish the spring semester at the end of May and immediately transition into a three-month paid internship at a farm somewhere in the city (or at the Chicago Botanic Garden). This is where the rubber hits the road and you get that serious, full-time, daily experience of being a farmer. Previous sites have included City Farm (from which Rick Bayless gets a lot of his vegetables) and the rooftop garden at Uncommon Ground on Devon.

Hopefully, I will graduate in October with a full growing season of experience, a final project in the form of a full farm plan, the concrete beginnings of a business plan, and a bright, burgeoning love of all things Urban Agriculture (I already have this). So far, Kristl has called me a nerd about 1,000,000 times and has been incredibly supportive of my quest to learn how to grow all the food for the rest of our lives. (Ideally, I would be able to at least significantly reduce our fruit and vegetable budget.)

One of the primary goals of the program is to take folks with unclear career paths or a desire to improve the food system but no related skills (that's me!) and prepare them for full-time work in urban agriculture. So, a big part of the final portion of the program, after the internship, is focused on helping participants explore what that looks like for them. As you may have guessed (since I have a Masters in Education and collaborate on this blog about sustainability), my goal is to educate people about food and how to grow it. I want to find ways to teach people how to grow their own food in whatever spaces they have and become more self-sustaining in an urban environment. (I recently read a statistic that said most major cities would completely run out of food in about three days if they lost access to their usual food supplies. We need to have a back-up plan.)

My career path could take many different forms, from individual gardening consulting, to starting a small education-focused urban farm where adults could take growing workshops. Hopefully, I would be able to take my passion for food out on the streets and give people the power to impact where their next meal is coming from.  I am personally inspired by the common proverb, "Give a man a fish, and you feed him for a day; teach a man to fish and you feed him for a lifetime."  It seems cliche, but even a good cliche packs a philosophical punch now and then.  What good does it do for my neighbors/friends/community/city for me to know how to farm and grow delicious food when others cannot? In so many economic models, it's not wise business practice to share your secrets and your essential professional knowledge, but there is so much to lose by not sharing that knowledge when it comes to food.  The food system we have now cannot be sustained, and this queer aims to be one of the few with the know-how to pick up the pieces when it does fall apart.

Regardless of how I proceed professionally, all our friends (and readers) are welcome to contact me with questions about WCH and my experiences. If you are already planning to grow your own food and want some (almost!) expert advice, I should be able to provide it, if not for 2014, definitely for 2015 and beyond. I'm just really freaking excited about increasing food literacy and food sovereignty in Chicago, and if that excites you too, let's make a more sustainable city together!

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