Monday, September 24, 2012


Growing our own food in Arizona is totally doable, but a challenge. The best way many people in Laveen have found is to flood irrigate. Which they say actually uses less water than the drip systems, but which still uses quite a bit of water. I looked around and discovered a lot of people having really great results with aquaponics. So far I've mostly been studying about aquaponics from a distance, but this weekend we made a concerted effort to get some things set up and growing. Of course this means everything I say here should be taken as me thinking my system through. Take it with a grain of salt please, and I will keep taking photos and posting them as we continue setting things up and see how they work out.

Aquaponics is when you utilize the water fish are living in to water plants, and the plants clean the water which you then put back into the fish pond, tank, etc. There are many variations on this theme, but that's the basics. There are some very good sites and articles online, and some decent books to read on the subject. Once I'd read all I felt I could take in, I needed to get more hands on and look at real life systems that were working to grow food people were actually eating. I've been fortunate enough to find some good meet-ups in the area which allowed me to see a variety of systems and decide which route we'd like to try here.

There's another aspect to Aquaponics that I'd like to include, which is fish food. You can grow duckweed and you can even raise red wigglers both of which can be fed to nile tilapia, one of the popular fish to raise in Phoenix since it is normally so hot around here. If done right, it can be a pretty complete system, so that theoretically you wouldn't really need to even buy fish food.

Of course I'm starting my tanks in the cooler time of year simply because that's when Carlie and Patch had vacation time together, so we decided to have a stay-cation and work on our sustainability efforts at home. Today we bought a 55 gallon food grade plastic barrel cut in 1/2 for grow beds, and a large IBC water tote with the top cut off so the bottom becomes a large fish tank and the top becomes the grow bed area.

Now I am left with a bit of a conundrum, and trying to decide will I heat the water, or start off with one type of fish that is good in the cold and larger, then move on to tilapia after it warms up again. Now, it's still in the 100's during most days here, don't get me wrong. Fall in Laveen, Arizona is not that chilly. But the water needs to be around 70 degrees for the tilapia to be happy, and in a couple months it will be hard to keep it that temperature without heating the water.

I've thought of a few ways to deal with this. I have thought of pumping the water from the tank up to the plants, then collecting the water the flows out of the tank in a black pipe which curves around in the sun warming the water and eventually puts it back into the tank. Basically a solar water heater specially built for the tank. That would allow me to keep tilapia in warmer water, but I might still need to heat the water for part of the year. It seems to me, it would be easier to just start with a fish that does better in cooler water, and then when it starts getting too hot for that fish, eat the cold water fish, and switch off to tilapia. After all, we're talking about raising food here. Not just the plants, but some of the meat, in this case fish. I'm thinking perhaps trout, or something which we might be able to also keep inside year round. More investigation is necessary.

In the beginning we don't have to start with fish in the tank, so we can actually put the plants in first, and get the water flowing properly and work on sorting out that part of the system first, then add the fish later. We'd like to have our system up and running before Patch and Carlie go back to work.

We've decided to have 2 Aquaponics tanks. One in the living room since we already had a fish tank in there, and one in the backyard in a semi shady area. When the hot part of the year hits, we may need to bring some shade cover in for the back yard tank like these guys did, but we may not. We'll see how it goes.

Inside we're using a 60 gallon fish tank to hold the fish and water, and a 55 gallon food grade plastic barrel which has been cut in half to hold hydroponic medium, plants, and possibly some red wigglers. Outside we're using an IBC tote with the top sliced off. The bottom is the fish tank, and the top is where the plants go. We could put hydroponic medium (rocks or clay balls) up there, but that's pretty expensive so we decided to fill the top with water and float a piece of foam with holes in it on top, and then put the plants in small cups poking through the foam. We'll see how that goes! More pics coming soon.

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