It depends on what kinda catfish you have I have 2 columbian sharks and a picktus catfish and I feed them Flakes (omega one natural protien foumula which they like) Shrimp pellets and occasionally i will feed them algae wafers i was told to get them because i got a couple snails but they also eat them (as do my mollies lol.) and i had Some cichlids and i bought them Cichlid Bio-gold and its also for carnivorous tropical fish and my biggest columbian(2.5 inchs) goes crazy for them. I hope my little bit of information helps you out
