I bought two occelaris and two perccelaris at the same time and put them in a 20 gallon. One occelaris became female but was a real bully to both perccelaris so I moved the two perccelaris to my 72 gallon. About six months later neither perccelaris became female so I moved the male occelaris to my 72 gallon to force one of my perccelaris in to a female. My perccelaris did the same to the occelaris for about a week or more but now everything seems to be ok. Still no sign of a female yet. I talked to my LFS first be for doing this because I didn't want a dead clownfish. My situation may be unique for all were together at first separated then reintroduced.