trying to breed? wouldnt you need like....3 females and then like...8 male blue jacks so they could pair off? i had a female with one of my blues and she always rejected him, so i tossed her...haha jk...i gave her away tho.
Trick is get a male normal Jack Dempsey, and mixed it in with several female blue dempseys. From what I understand, the male of the blue dempseys are sterile, because the person who breeds them in So. America wants to control the market.