Very.... I eventually had to remove him. He got huge (5” about) and got more brown and less black as he grew. I had to catch him with a fish hook to get him out. I took him to my LFS and they dumped him in their 250 DT where he terrorized their fish for nearly 10 years. I went in one day to find he had just vanished. He certainly wasn’t beaten up by the other fish. He didn’t jump. No fish got sick. They think he died of old age and fell behind the rocks somewhere.That looks like terror.
How old did he get?