I have the catfish in my sig, plus a couple of tiny ones that I couldn't fit in. I'd have to say that on an average month my biggest catfish(depending on his mood) can eat around 20 lbs of shrimp, fish fillets, and cichlid pellets by himself. I think I average a two pound bag of shrimp every other day between all my fish. I find deals where I can, and during the summer I trap small fish and crayfish to cut down on costs. Winter kills me. I have around 18 catfish total, and their total weight combined would be over 100 lbs. So my food bill for just the catfish would come out to around $100-$200 depending on how well they eat. I don't regiment how much they eat. I just feed them till they are not interested anymore. Some only get fed once per week and other every five days, and some every day. Hope this helps