Fuzzy stuff on Zoos

[cichfreek]

I have what looks like a white mildew growing on one of my new zoanthis rocks. I've tried a Lugol's dip and a Seachem Reef Dip, but this stuff just keeps spreading...any thoughts?

 

[ccCapt]

Sounds like some kind of fungus. I had something similiar on my zoos awhile ago and cut out the parts that had the fungus. That stopped it and the remaining zoos grew and filled in the open space on the rock.