You can sex pretty much any fish at any age by venting them do a search on venting. basically on the under side of the fish there is the anus and a vent typically the female has a larger vent hole female Oo male oo . This is the only true way to tell 100% for sure. Here is some info http://www.fishhead.com/articles/ventsex.htm next time start a new thread you will get better feedback.
