I've had the same four in my 5' 150 gal for years now - Coral Beauty, Lemonpeel, Cherub, Eibli. Plus I usually keep a juvenile regular angel until it outgrows the tank (currently, a Koran.) Are there skirmishes sometimes? Yes. But usually nothing too serious. The Lemonpeel is by far the biggest/meanest (Bicolors get nasty too.)