The only sure fire way(for myself
http://www.fishforums.com/forum/imag.../icon_wink.gif
) is to just wait until she is holding. I've read something about being able to take the fish by hand flip them over and check out their underside. I think its called venting but I may be wrong. someone who breeds will know. I do know that you cannot go by eggspots. I have a OB female that has eggspots.
Hey what do you know, I was right. Stand back!! Head beginning to swell!!! LOL
http://www.cichlid-forum.com/articles/gender.php