I've had this model citizen for quite awhile. He is quite big. . He is the only tang and the only large fish in tank. I have 2 tiny clowns two pygmy angels and 5 chromi in a 100+ system. He has become quite aggressive over last two weeks. I've noticed as coral encroach on his swimming path. He is ripping apart everything in that path. Ive spun rocks to clear the way. Is this normal as they age. Extremely well fed. He waits for hours were clip goes. Any words of wisdom. I've googled it not much out there. Ive got coral pieces everywhere.