Ya I'm not sure. I had this GT and a Blue Acara. They bred and this GT protected them like crazy and started to beat up the Acara so I removed it. Most of the time, it's the male who protects and ends up beating up on the other fish in my experiences. So I thought it was a female. Then I see all of the male GT's and they have these huge humps and mine has nothing. Them pics are even older and she doesn't have any hump, so IDK. I think it's a female, lol.