Help ID are they a problem?

[seanothon]

I started noticing these little things a few weeks ago and they have begun to spread all over the tank. What are they and are they a problem?
Can't figure out how to put pictures up. find them here:
http://www.reefcentral.com/forums/sh....php?t=1846239

 

[shrimpy brains]

I can't seem to access the pics, but it looks like you got your answer on the other forum!!

 

[flower]

To see the pictures it wants me to join???