I started both of my systems with Tilapia, they died at 54 degrees F.
They were replaced with Gold fish and later a Koi too big for a friends small pond.
Another friend was rebuilding his Fish Tank and gave me his Catfish and Perch. They survived the winter well and got large. Dave Pennington helped me drain the system and weigh the fish. We had 30 pounds between the two fish tanks. Not much if you are raising fish to eat but my intent was to raise just a few as the engine for my Aquaponic systems.
Dave took the biggest fish to the Richardson High school system so their system could be started. I still have a 15 pounds of Catfish and Perch split between two systems. One of the Cats is about 5 pounds, quite a beauty!