About anything in the water that looks like food mostly meat eaters which is other fish, mostly, but will eat nearly anything else that has meat on it. If you have one that you need to feed, hamburger works as well as some of the dog foods that are out like homestyle Kibbles and Bits. DO NOT over feed. Just put enough in that it will eat other wise it will brake up and cause alot of sediment. An individual fish isn’t prone to the “feeding frenzy” as a rule but just don’t stick your finger in the water. Their bite for a full grown one is the size of a half dollar.
Hope this helps