Saturday, December 25, 2010

Aquaponics Update

I'm about 6 months into the aquaponics experiment. My first system, looked great (IMHO) and worked pretty well until it sprung a leak in the grow bed. I'm pretty sure this was in the drain area. I unfortunately placed the drain near a seam in the EPDM, which wasn't in itself a problem except that one side was regular thickness and the other was double thickness where the seem was and I think that caused a tiny leak that ended up making the wood swell and cause a big problem. Lesson learned. I didn't lose any fish, but I had been wanting to try an IBC system anyway. (IBC's are the giant plastic 275 gallon containers that things like bulk pineapple juice and liquid soap are shipped around in). These are a couple of pictures of that system.

I have the fish tank section shaded to prevent too much algae growing in there so it's a bit hard to see in these photos. I cut the 275 gallon container into two sections, an approximately 175 gallon fish tank and a 100 gallon growbed which is filled with hydroton (expanded clay pellets-- very lightweight, easy on the hands). The grow bed is mounted on top of a structure I built for it made out of 4"x4"s and 2"X6"s. It's on casters like the original system. Right now, because the fish need to stay warm I keep it covered in greenhouse plastic. One interesting thing I learned was that, even though the temps in the grow bed get up above 100˚ during the day, the greens don't bolt, presumeably because of the 68˚ water flowing over the roots every half hour. I keep a 250 watt tank heater with a built in thermostat in the fish tank just in cases the water starts to drop at night.

Growing tilapia

conrete reinforcing wire being used as a structure to support the greenhouse plastic

So far I'm impressed with how aquaponics is working out. These plants have no supplements of any kind, they are strictly being fed with fish water.

P.S. Now I'm working on system #3. The 400 gallon pond is nearly complete...


Ben said...

Could you use broken up clay pots for a growing medium?

Sean-Michael said...

that's awesome! I can't wait to hear how that is going. Did you find the water ever getting up over 68 degrees in the day time?