Yep. Had a gougous one that ate like a horse stayed hidden all the time and only came out to eat. Also hated all other fish and killed a Harlequin tusk and tried to kill a Yellow Tang bbefore I sold him.
IMHO a gougous fish, but a fish that eats all the food, stays hidden, and will not allow tankmates was NOT for me.
I had a 240g 8' tank and he wanted it all to himself. For a species only tank a great fish, but thet stay in their caves all day.