A Question about Clown Fish

[GavinWang]

I have two Ocellairs clowns, both of them are 1.5 inch. They have been in my 10 gallon tank for 1 month and half now. They were peacefully toward each other until a couple of days ago. One of the clowns keeps biting the other one, and the weaker one losts many parts of his fins. Any suggestions on what should I do? Should I separate them or should I just leave it? Thanks for your help.