Venting is the most reliable way to sex cichlids. It helps to looka at as many as possible to get comfortable with this method. Wide spectrum light and a jewelers lupe also help; I personally like to use natural sunlight when possible. I take (4) five gallon buckets with the fish to be sexed in one and water from their tank in the others. One is used for unsexed fish, next for males, next for females and the last for the undecided/marginal specimens. I handle each one carefully with wet hands and slime-coat handy, no more than 30 seconds out-of water. I turn the fish upside down and look at the vents right before the anal fin on the underside of the fish. What you are looking for is a small fron vent and the second, which is closest to the anal fin on a immature females will be a little larger maybe a differant color, sometimes pinkish females instead of greyish in males. mature females and one that have spawned have larger opening's which should be readily appearant. If the individual is borderline sexable place in the unknown bucket to rest and wait till all others are sexed, then go back to these. This sometimes takes a little getting used to, but the more practice you get the more comfortable you will be.