Well today, after researching countless threads and websites, as well as advice from cichlid keepers from the cichlid forum, I got an opaline gourami to put in my 40 gallon. Well I was worried that my convict especially, and possibly my jewel, would be after him and stress him out. The convict doesn't care for him, and only attacked him during feeding (but he attacks everything in his way during feeding) and my jewel chases him but not persistently. To my surprise, my baby pumpkinseed is chasing him around the whole tank! This tiny little fish who I rarely even saw before is now terrorizing a fish more than twice his size! And he hasn't even reached sexual maturity yet! I even saw him peck at my convict today, but my convict showed him who was boss. I'm kind of scared now about when he gets a little older, although he wasn't staying in there too long anyways. But for anyone out there thinking of keeping sunfish, I highly suggest you keep them with each other or with very VERY aggressive and tough fish. Just imagine what my pumpkinseed could be doing once he reaches his max size of 8-10 inches!