LOL@Allan. I don't feed fish to my fish, I feed fish to my eels. But my fish will eat fish, including the live ornamental kind that I paid good money for :P

If you decide to feed fish flesh, the most important thing is that it be a saltwater fish. Freshwater fish lack essential nutrients that our saltwater animals need. I normally bring back a bag or two of frozen "leftovers", from when I clean what I catch at the coast. It's almost always a combination of speckled trout, croaker, gafftop, redfish. Sometimes I cast net for piggie perch and small mullet. My eels love those.