I like the idea of convicts however I wouldn't want them to start breeding because they would become so aggressive and I don't want to start breeding fish yet, but I was wondering would two males get along and also would two male firemouths get along?
If you are thinking of something more common, then either firemouths or cons are the way to go. First, 2 males are not a good idea. Second, I think non-breeding females are better looking than non-breeding males, so I would go with a few female cons.