+1 to this, any Acanthurus tang is a nightmare with aggression. Just some are SO much worse than others.
The worst tangs for aggression IME (And over here we rarely keep the larger Acanthurus tangs such as dusumieri and fowleri) would be:
1. Sohal
2. Clown
3. Achilles
4. Both PB Tangs
5. Atlantic Blue
In your experience that Achilles aggression is indiscriminate against any and all tangs or worse against Acanthurus like other Achilles, powder blue and powder browns?