I think you'll find both answers. I have two (and a third one in waiting) who are inseperable. I don't know if this had anything to do with it, but the first girl I got was larger than the second and I think she took on the dominant position from the start, but never did more than flare for the first few days. Now I have my third which is currently being introduced to the tank and she is much smaller than the other two. They've checked her out, flared, but are now doing their own thing. I'll keep and eye on them for the next few days, but I think they will all be happy together. I kinda think of them as a little sorority, where they'll show their dominance to the newest member and occasionally flare up to one another, but overall they get along really well. The main thing, just keep and eye on them and make sure one of them isn't overly aggressive. Good luck!!