Torch coral tissue recession?

[SwimsWithFish2]

Hello! I've had this torch for almost a year now, and all of a sudden I'm noticing some recession. Nothing has recently changed, all levels are good, nitrates at zero... Only thing that's different is I've started dosing H202 to fight a horrible GHA problem. Please help.

 

[SwimsWithFish2]

Bump

 

[kevin32]

maybe the GHA is bothering it? Have u try remove it and inspect for parasites?