sexing bolivian rams

Question
i have 3 bolivian rams in my tank and i would like to know how to tell them apart. i dont know if its relevant, but one of them that i bought today has more of a slope to its back than my original one (my original one has more of a straight back).

thanks

Answer
Hi Sarah,
  While there are differences between the sexes, they are pretty subtle and you need to have looked at a number of these fish (many dozens) to know what to look for.  Males are typically a little larger and often have larger, taller dorsal fins.  So if you have only three, that does not mean that the largest is a male and the smallest a female, though there is a chance that that is true, moreso than that the largest is a female and the smallest is a male, particularly if they all come from the same batch.  Males also have a more robust head and face, though this difference if very subtle.  

-- Ron C.
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>