I actually had them shipped so I don't know how they were kept. Also, they started doing this as soon as I put them in the bucket to acclimate them! The smaller one already has small nips in his fins. I feel bad for him.
One more thing, the bully (larger one) has thicker black bands than the smaller one (presumably the male). Is that one way to tell between males or females or is just a normal variable between fish to fish?