Jack dempsey gender

Not sure, but a great looking JD and he/she probably isn't fully comfortable yet.
 
FF is right, it's a very nice looking JD!

What size is it? If under 2-3 inches it can be hard to say.

Do you have a rock or wood "cave" big enough for it to claim as a territory? I see it trying to hide in the plastic? plants in 1st pic.

How big is your tank? Males can grow to close 8 inches, females are smaller. Try for pic that shows the tail, dorsal & anal fins clearly (pelvic fin too), that will help tell its gender.
 
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