We have a molly that gave birth about 4 - 6 weeks ago. 9 of the babies survived. Recently within the last week or so the baby mollies have been biting the adult male. I feed them regularly so they aren't hungry. His side is all biten up and he has a little dip by his top fin where it looks like a chunk got biten out. He is now swimming on his side now. Why are the baby mollys biting him?