As my fish have grown and my system has proven to work, I have ordered some tilapia fry. I received 25 fish from a guy I met on a aquaponics forum. They are a mix of blue and pink tilapia and probably are a hybrid of the two. Since I got them for under $50 instead of the normal $250 I cannot complain about specific breeds.
Now I need a larger tank so I had to make an entire new system. I bought two “under the bed storage boxes” on clearance and added some screw in bulkhead fittings to the sides to allow water to be pumped into and drained out of the tubs. I had a problem with my hydroton being sucked up into my fittings so I took some ¾ pvc pipe and wedged it inside the interior fitting using Teflon tape. I cut several drainage slots around the pipe to allow water to flow, but to keep the clay pebbles out. I also cut 18 holes in each tote lid to hold more plastic cups.
The hydroton in the tubs give the bacteria a place to live, as well as bulking up the tanks so that the pumps don’t suck the large aquarium dry before the tanks start to drain. I have a valve, as well as a timer, to ensure that I have several complete water changes every day, but never take the aquarium down past half full. This took a lot of trial an error. If your too aggressive with water changes you may overflow your grow beds onto the floor. If you don’t pump enough water you will let too much ammonia build up and hurt your fish.
I am pretty satisfied with my setup even though I still tinker with it. Right now my biggest problem is the light spectrum on my grow lights. They give me pretty great vegetation, but no flowers. Maybe that’s why leafy vegetables are recommended for this type of set up. No matter, my fish are growing like crazy, and in a couple more months I am going to have a fish fry….