Bacteria Disease in my toadstool? A hole appear

[Aqua Splendor]

Hello,
Couple weeks ago I notice white spot on my toadstool and couple weeks after a hole form.

(pic taken the morning when coral sleep)

I had a problem with one of my red sea coral pro salt and I had to switch the salt, the white spot appear after this.
Another thing, I cut the flesh by accident on the left part around the same time frame. I don't know if bacteria could have gone inside and make it sick.

It seem to recover but those white spot is something I never experience before, any though/suggestion?

 

[Tahoe61]

Means of reproduction, lateral fission.

 

[Aqua Splendor]

OOoooohh I hesitate to talk about that, wasn't sure at all, thank you!
I setup a Coral frag just for him, he doesn't fit in my tank anymore, getting squeeze everywhere.