I have a problem with a Bangai Cardinal biting my 13 year old Pyjama Cardinal. The Bangai was added 3 months back after a friend shut down his tank. The Pyjama know under my huge Monti and the Bangai harrasing it all the time. I dont jknow how strong the Pyjama Cardinals are and can take the hiding. The other problem I had is sorted after the Powder Blue suddenly started fighting with my 13 year old Tomato Clown, finally chasing it out of its territory behind the tank. That fight carried on for coulpe of weeks but the Clown hard as nails.