Well I got the Ok from the girlfriend to get another tank that will be bigger than my 30 gal. Debating between a 55 or a 75, and I think the 75 is winning. Well I'm also looking for more fish. Right now I have a molly, and a good number of guppies. Would y'all think with a good sized tank I could get away with some semi aggressive fish with peaceful fish? Or should I just go ahead and make that next tank into a cichlid tank?