Have one in 55 with some rock that he hides in ,I feed him 2/3 times a week till he loses interest in the food (cut up scallops,krill,strips of fresh fish)in the same tank I had a few green chromis,large maroon clown ,marine betta,he has not bothered any fish,snail just keep well fed ,by the way he's at least 18" long head about the size of thumb good luck.