Whats happening to my live rock?!?!

[dragonet123]

Hello everyone!
I just got my live rock, about a week ago, from liveaquaria (http://www.liveaquaria.com/product/prod_display.cfm?c=393+2392&pcatid=2392) and I noticed this grayish fuzz on it. It looks like mold. I dont know if this is good for the live rock, or should I scrub it off? Please help me. Here some pictures of it, sorry that the pictures are blurry.

 

[Aquarian]

Filter feeding sponges,and tunicates let them grow they help filter nutrients from the water.

 

[salt_for_brains]

+1

 

[reeffreak]

I'm going to go with decaying matter.Remove the rock and scrub it off if you want.