Sexing The Dempsey

Well, I think your Dempsey is a male judging by "his" lower fin shape. Sometimes when you have 2 males, the smaller weaker 1 will try to look & act like a female to avoid getting killed.

What size is your tank? & what size is the other Dempsey? Can you post a whole tank pic?

"he" has some split fins, I think it may be being picked on by the other 1.
 
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