Probably a Purple, Yellow, or Scopas Tang. These guys along with Powders can be very aggressive. Purple Tangs are up there in the aggressiveness. Powders can be aggressive and bold as they mature so you'll need tangs that can keep up with them. Just remember to put tangs of the same genus in at the same to avoid territorial issues or you'll have to move your display, so that they can establish new territory and also, put the most aggressive tang as one the last fish you put in your tank.
I've always had bad luck with powders. Sometimes, when you just look at them, ich spots pop up right away! Beautiful fish but very delicate.
I've always had bad luck with powders. Sometimes, when you just look at them, ich spots pop up right away! Beautiful fish but very delicate.