I would stock that thing with 1 pearsei cichlid and a bunch of small-mid sized cichlids. I have a 120 48x24x24, same thing exept yours is much taller. That is a nice tank, is it a new setup?
I think the 150 talls are 30 inches tall. The good thing about tall tanks is that you can have the aggressive fish that bullies on a certian depth of a tank and he dosen't see the other fish in a diffrent depth.