Ive had my tank running for almost 8 months now and ive only had 2 fish occupy it. The first is a Oscar Cichlid who is about 8-10" long and a Feather-Fin Catfish who is pretty big himself being 8". They have gotten along pretty well and only chase each other every once in awhile. I want to introduce some new fish into the tank but im not sure what to get that could be a good tank mate with these two. The Oscar Cichlid can be very agressive sometimes especially when I feed them. I don't want to buy the wrong fish and end up seeing it die. Any suggestions?