What is this?

[Hawaiigold]

Anyone has an idea what this could be? Started showing up a few weeks ago. It's slowly getting more. It doesn't seam to move.
Is hard to scrape of.


Thanks for any ideas what it is or suggestions.

[url]http://reefcentral.com/gallery/data/500/170165IMG_0112.JPG[/URL]

 

[BLKTANG]

No picture in the link.