I will say. stress level is a main factor in my experience. i had a tiny 2" male in my 125g with my monsters. he had escaped my attempts to seperate him from the tank and for 3 months he swam around with the big guys. his fins were black, he had not even a bump and didnt grow a cm. i recently switched him to a grow out tank where hes boss and in less than 2 weeks he has a nice kok coming in already. i didnt change the diet either just tanks and stress levels. before i would have said he was a low grade but now he has potential to be a stunner monster of a fh with a huuuge kok. i feed high protein pellets, color flake with that axanthhin whatever stuff and lots of frozen foods varieties among other things.