i have one my self and they are one of the more docile eels but they are still an eel lol. if you miss a day in feeding them they start to hunt for any fish they can swallow whole mine has eaten 4 fish. i tried doing some little fish like a cleaner wrass, bicolor dottie back, fire fish, and clowns but he ate them, even one of the clowns. but he wont toch any larger fish like triggers, angels, and even large tangs. but if you keep him feed you wont have any problems. as they get older they dont get meaner they just get bigger and can cause more damage.