BAD CLOWNFISH!!!

So, I went on a contorlled buying spree today and came back with a wrasse (the six-line type) and an orange starfish. this tank has been going for about 8 months now, and has been staqble for awhile, although I would not trust my limited experience as far as I could throw it. So, after adjusting for a couple hours, i threw in the wrasse, which was not on its best behaviour and became rather obnoxious. Reading that orange starfish take awhile longer to adjust, I added it a couple hours later. Shortly after, the starfish was doing well, moving around, and doing whatever starfish are supposed to do. Suddenly my tomato clown decided it didn't like the starfish and tried to bite off one of its legs on three occasions that I witnessed. The star has now climbed to the top of the tank in what looks like an escape plan. Is there some compatability error I was not aware of? Is the clown just in a bad mood with the new additons? Is it menopausal? I would appreciate your feedback.
Thank you!
Kevin