My Buttis play nice, i have a male green terror in there thats about 8 inches too and he keeps them in check they are really really really really afraid of him, my dempsey is also the ultimate BOSS in my tank, not sure if my Butti's will ever test them, they are pretty much afraid of those two. i have read that Buttis are very aggressive but i just dont see it. i had a texas cichlid that was killed by one of my butti's but thats about it. i dont see all of the uproar about how aggressive they are. maybe i havent seen it yet. maybe they have more growing to do before they get where they should be with the aggressivnes.