Aside from the obvious huge bulbous forehead the males get, how can you sex these guys, and at what size? I have [had] a group of 5, two grew a lot quicker than the rest, and one got a really large hump at around 8cm and started picking on the other larger one. I figured it was the dominant male picking on the less dominant one, but since I've removed the one that was getting picked on the big male is being aggressive towards the other 3, who are all considerably smaller, don't have the long fins [yet?] and have no signs of a large forehead.
What are the chances that I got unlucky and ended up with five guys?? I would have thought by now if there was a female in there the big male would be trying to get it on...

What are the chances that I got unlucky and ended up with five guys?? I would have thought by now if there was a female in there the big male would be trying to get it on...