He chases her, I'm not sure if he is nipping, she has no marks. Everytime she comes out of hiding he charges her, and almost pushes her back into a corner. She is not allowed to leave that corner. I was trying to breed them, but I won't let her be hurt. They were in a 30gal, and it is well planted and has caves. He is now in a 10gal(Temporary), and she is in the 30gal. She is still being really shy, where she used to be out going and come and greet me with her feelers, feeling along the glass where I put my finger, but now she is just hiding. I hope she comes around. I have heard not to put males together but thought a male and female would be ok. I guess not though....