How old are the ciclids? Ciclids can be hard to tell which sex they are until they mature. For example, I raise a couple Oscars and it is very difficult to sex them even after they reach maturity at 1 1/2 years old. Sometimes you may tell by size, markings, growth rate, and/or behavior; but, these signs are not guaranteed by any means....
Good Luck..
Sorry I couldnt be more help