I didn't think they were supposed to be aggressive. I've had Bettas since I was a kid(first fish was a Betta) and they weren't half as mean as Chameleon. Dracula is the only other guppy he gets along with. Everyone else he tore their fins so badly they couldn't swim or the actual attack killed them. I purposely got guppies because they were supposed to be community fish. The only thing I could put with them that didn't get nipped to death was those red tailed ones I took back. The frogs were with them but now I see they were very unhappy with the guppies. What should I do with Chameleon?