My Garra Rufa(Dr. Fish) keeps chasing my platy! When I got him he seemed to not be aggressive at all. He doesn't chase any of my other fish, he's only been in the tank about 2 weeks. Is he just playing, or is he being bossy? I've heard that they love to boss other fish around. He's one of my favorite fish, and I don't wan't to get rid of him.