I recently watched a show on some cable network. . . I think it might have been Countdown to Armageddon, or something like that. One of the families profiled had turned a backyard swimming pool (in-ground) into a very nice ecosystem. Tilapia were being raised in a small pool in the deepest part with hydroponics and chickens above, I think. I got the impression that it was very easy to raise the tilapia, and it made me think about trying to start a small pond, myself.