I have a relatively small system which has undergone many changes and transformations over the years, adapting to changes in design, weather, and many other varied conditions which have had a profound affect on the systems success.
The basics of the system today can be illustrated as follows:

Assembled and running it looks like this:

I guess its better viewed between harvests where there are stragglers:

The system is based off a 330 Gallon food grade IBC Tote. I cut the top off as most people do but rather than setting it on top, I raised the main tank up onto a stand and placed the top underneath as a sump. I initially ran overflow from the top tank to the grow beds and then return to the tank. I found this difficult to evenly distribute the water to all my growbeds equally and consistently so I have since moved to a pressurized system from the sump.

I keep about 75 Tilapia of all sizes in the system along with a 4lb Picastomus catfish. they do very well in the summer however in the winter the water temperature starts to get a little cold. I wrapped the entire tank/sump in insulation and this made a big difference by itself in keeping the water temps from swinging too much. I added a Brewers stainless steel wart chiller in conjunction with a home made solar panel to help keep the temps up. It does a pretty good job and because its a sealed system I don't have to worry about heavy metal contaminates or other issues mixing with the water and the fish. I also have an electric solar panel, battery, charge controller, and a 12v pump driving the solar water panel. This automatically turns the pump on when the sun is out, and off when it is not, completely off grid.


I used Grow Stones as media in 6 beds. I had bell siphons for a while, then switched to timers for a while, then switched to constant flood and haven't looked back. For years I have used the grow beds as my solids filter, introduced red worms and all has been well. However, every summer when the water transitions from the high 60's to the upper 70's, any waste buildup in the tank/sump goes into a bacterial explosion for a short time and the CO2 skyrockets which has caused fish die offs in the past. You can see them gulping from the top of the tank even with an air pump running 24/7. Because of this, I ended up adding a radial solids filter to better manage the waste and reduce maintenance on the beds.
