Hump? You mean the bump that alot of male New World Cichlid's get in maturity?
If thats what you mean than it just means he is asserting his dominance, especially if he has a mate in this community. With most animals, the dominant male forces others into submission (whether the other animals are the same species or not) to allow him to choose his pick of food first. This is all about tank hierarchy and just his natural instincts at work. Though rams are smaller than most cichlids, they still are cichlids none the less, and will bully the smaller tank mates to show them that he is the dominant fish of the tank. If you don't have a pair now and wish to pair him in the future, then you might want to change your tank mates or get a bigger tank as he will only become more aggressive to protect his female and territory.
