Toadstool Trouble or not?????

[E fishn C]

I've had the leather Toadstool for about one year now and there always seams to be some bright white areas on its edges. is this new growth, bleaching or something in the tank nibbling. She's located up top. I had some salt creep fall back in tank when I was cleaning class canopy. Salt burn? Have you heard of this?
Anyway, pictures are attached. Any help would be most appreciated.

Water parameters
54Gal
Ammonia 0
Nitrates 20
Nitrites 0
PH 8.4
ALK 200
Ca 440
Temp 79.7
Salinity 1.025

View attachment 268397

 

[Aaaron]

I have had the same thing, and it continues to grow and grow

 

[Doug]

From what I can tell from the pictures that you posted, it looks like growth to me.

 

[E fishn C]

Is everyone in agreement this is new growth or as a dermatologist would say "you have POS" (Pis** Off Skin)