Sexing my Jack Dempsey, please help!

[echoxiaolixia]

Hello all! I have 2 Jack Dempseys. They are about half a year old. I bought them at the same time. Then one fish, Bully, is growing twice as big as another one, Nemo. Bully has this name because it always attacks Nemo. Even though I built 10 caves for them at the bottom of the 30 gallon tank,Bully drives Nemo to the one upper corner of the tank and Nemo stays there most of time while Bully is freely browsing all the caves and the entire tank. So I was thinking maybe both of them are male. However, recently, I saw them get together recently to do the belly dance, and Bully attacks Nemo less. So I am thinking maybe they are one male and one female. Additionally, their color and shape are distinctively different. Bully is so beautiful and big, and Nemo lacks color and has black strips on both side of the body and way much smaller. They look so differently that I almost feel that they are not both Jack Dempsey. I am thinking maybe Bully is male, and Nemo is female.

Please see the pictures below of Bully and Nemo. Can you please help me to identify their genders? Thanks!

 

[Rbishop]

Think you may have to wait awhile for identification on physical coloring. You might be able to tell by venting.

 

[orcace]

Bully is awesome, nice fish.

 

[Vicious_Fish]

They both look like females to me. The reason Nemo is that color is because she's stressed. I'd rehome her or pick up a larger tank for the two.

 

[echoxiaolixia]

Thank you all. Bully is a total beautiful. Even though Bully attacks Nemo a lot, a lot of times they also hang out together and rubbing each other's body. Will two females do that?

 

[echoxiaolixia]

This is a picture of Bully and Nemo hanging out together. They then will rub each other's belly for a little, then Bully will chase Nemo away.

 

[echoxiaolixia]

Also, the brown scar on Nemo's head has been there forever. Will it be a disease?