Something Wrong with Miami Hurricane?

[Shy519]

There had been perfect circles of tissue missing from the chalice for a couple days and now, upon turning the lights on this morning, almost half of the chalice is dying. The first image is the first circle to show up. There was about 4 in total and they had begun healing last night and there was a lot of hope that whatever caused it stopped. The second and third images show what it looked like this morning. What could be causing this? My stock include a blue damsel, scooter blenny orange spot goby tiger pistol shrimp, porcelain crab, peppermint shrimps, several hermits, and two very large turbo snails.

 

[Shy519]

Just realized I called it a Miami Hurricane...it's a Hollywood Stunner

 

[avijay_23]

Any other coral close to it which puts out long sweeper tentacles at night. Looks like it may be stung by another coral. Alkalinity crash may be another cause. Any other sps or lps showing similar effects? Try moving it to a different spot
None of your livestock readily account for this.
Good luck.
Vijay