Montipora Turning White

[jtess7]

My large montipora is turning white and I don’t understand why. My parameters are on point and my others are fine.

 

[Baldyreef]

it seems almost like something is encrusting over it?

 

[jtess7]

Yes, and I’m not sure what it is. I’m thinking of cutting it before it continues to grow more.

 

[KrisReef]

Agree with the above statement.
Almost looks like blue photosynthetic sponge in the picture. Or something else, like rot I would careful remove all of it to hopefully prevent it from spreading further.

A white light image of the stuff that you remove, or a magnified image from a scope may help with the identification of the object?

 

[jtess7]

Thanks!