I have a 46 bow with FW fish. They have been eating my SW flakes (my SW fish don't get them) and the leftovers from my SW fish for years. The FW fish came from my sister. Her one large gouramie used to get a red bacterial infection often. He has not shown any red since he has been with me. They get what is left from my SW tank feed too, which is loaded with vitamins every time.