When I had my wolf fish I fed him beefheart, earth worms and frozen silversides. He never ate pellets at all. He was a beast and needed a tank to himself... you really need to watch anything in the tank with them as they will take bites out of anything. I had a temperature reader that would suction cup to the inside of the glass and it came loose one day and was floating in the tank... as soon as he seen it over head he drilled it and shattered the glass all over!!! Whatever hit the water he would rip in pieces. These guys should not be mixed... IME.