red devil fish and jack dempsey fish

Question
how do you tell the sex of each of these fish?

Answer
Hi Nicholle,
  These fish can be a bit challenging to sex.  There are no 100% obvious signs.  Males tend to be larger and heavier built. Females have a rounder belly.  It is much easier to do after you have seen many hundreds of them. It is pretty impossible to do if you have only a couple of fish to look at.  

-- Ron C.
   rcoleman@cichlidresearch.com
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