Finally! I finally figured it out regarding the stinkin' Kole tang and the Coral Beauty. All week, I kept moving stuff around, putting in a net, moving the egg crate, changing up the aquascape, etc. to distract the tang. It would all work temporarily, but the Kole tang would start attacking again. The Coral Beauty didn't seem stressed and would immediately pop back out, but I was getting tired of it. Plus, the angelfish was confined to the right third of the tank...any further out and the tang would attack.
I remembered I had some mirrored tile in my "fish cabinet" that I had used to catch a difficult fish before. I cut off a piece and taped it to the outside of the tank wall furthest away from where the angelfish was hanging out (and hiding). The tang went nutso over that horrible tang in the mirror! :grinning-face-with-smiling-eyes: Tail flapping, backing into it, following it everywhere. The angelfish, meanwhile, was venturing further out. The tang would sometimes go after the angelfish, but then would rush right back to his mirror tang enemy. I did this yesterday afternoon, and this morning, the tang was still going after his imaginary "friend" in the mirror. I noticed that the angelfish was getting braver and braver, as far as venturing further out. We left for a few hours and when we came back, the angelfish was all the way on the left side of the tank and the tang had a big fin nip! I just hope the angelfish finally let him have it!
The Coral Beauty is swimming all over the tank now, and the Kole tang is hardly paying attention/reacting. I'm going to leave the mirrored tile up for a few days, just to make sure, before I try taking it down. If he starts attacked the angelfish again, the tile is going right back up!
Ironically, the story has a weird twist. I have an acrylic fish acclimation box that I've primarily used as a fish trap over the years. The last two fish I had to trap were my O. clown and a damsel, who were relentlessly attacking a new fish. I used the mirrored tile to draw them into the box and put them in timeout in my 16 BioCube for a few weeks. When I introduced them back into the 90, they were model citizens. The fish they were attacking??? That stinkin' Kole tang.
A few pictures! First, the Kole tang and his evil twin.
Never thought I'd see them this close together without an attack in progress!