If these came from where I think they did, then they came from a 70x30x5'deep dirt bottom pond in this county. I met the woman that owned the pond at my club's plant festival. These are not for eating! Tilapia's main source of food is algae. In a lined pond, they can't be seen. Mine have migrated now. They took the plunge down stream to be with the koi, goldfish, and shubunkins. If there isn't any algae, they will eat plants and, in one instance, eat smaller fish but they are primarily vegatarians.
Happy ponding,
Scott