So I guess I made the mistake of adding my Y.Tang too soon. I wasn't aware that it should be one of the last fish to go into the tank. (My mistake) It's been in my tank for about 4 weeks. I have a 65G, which I know is kind of borderline on a tang but I decided to at least try it for a while. The Y.Tang is pretty small. Anyway, today I bought a Banggai Cardinal and a Keyhole Angel. I was told that it's better to add more than one so the Y.Tang can't zero in it's aggression. I also turned the lights out before I added them, and they're off for the day. You think they'll be a problem? It already chased them around a little bit, but of course the Angel had to go right into where the Y.Tang sleeps... Anyone had experience adding fish after a Y.Tang? I didn't know they would be so aggressive to newcomers. :-/ All the parameters are good: Ammonia/Nitrate/Nitrite/PH/Calc/KH, etc. Tank has been going for about 3 months now.