Ok so i got one Dolphin Cichlid in a 20G high tank and its about 3 inches.. i was going to move it to my 50G with 2 common plecos(one is 3inch and the other 6"), 2 angel fish(like 4") and a dragon goby(7"). I have other fish in there but will move them to the 20G (non aggressive fish). I was wondering if the dolphin cichlid will pick on the Goby.