RD, I can't believe he is a she

#1
I thought I had a male red devil since its fins were pointed and went all the way to the end of the tail but much to my surprise, after I purchased a mate, a female, my original fish layed her eggs, even though there was no male and the new fish is still a juvy (3" long). Has anybody else ever had this happen? I guess I need to trade the female for a male. I felt bad for her. She worked so hard protecting the eggs and they couldn't get fertilized.

How big do the male RDs have to be to be able to fertilize an egg?

Any assistance would be appreciated.