he gets one every now and then.. its weird because he doenst stop attacking the glass.. and itll just heal up out of nowhere.. and your right i had a giant black rhomb and he had a chimple that was huge..
^^yup, huge chimples look pretty ugly on a fish, only way to stop it on a large rhom is a HUGE tank
when they are small you can just throw a towel over the side of the glass that he attacks the most (its usually one of the side pieces), and that sorts them out