Leptastrea -White Fuzz

[Matt3586]

Hello All, about 3-4 weeks ago I purchased a Leptastrea through WWC (Honeycomb variety). Though I'm new to Leptastrea I know it's been struggling quite a bit. It rarely opens, if I does it's for a couple hours at a time. Recently, I've found it growing white fuzz on two locations. In my research I've been unable to determine a cause. Is anybody more knowledgeable able to assist? I've attached a picture.

5 month old tank:
Kessil A360x
Ph - 8.2
Salinity - 1.024
Alk - 8.2
Ammonia - 0
Nitrite - 0
Nitrate - 0
Calc - 420

 

[vetteguy53081]

Appears to be sponge but unconfirmed under the heavy blue lighting in your pics
IF sponge, expose to air or inject with vinegar to stop it

 

[shakacuz]

picture under white could help. might be a sponge, as vetteguy mentioned.

 

[Matt3586]

Thank you both, here's a couple additional pictures.

 

[Matt3586]

Update: I exposed to air and no luck. The corals white spot has actually grown, this morning it looked like something was flaking off so I gently blew with a turkey baster. A slightly larger portion peeled off and floated away. The polyps on the sides are still opening? Any ideas would be appreciated. Thanks.