What is this?

[saltwaternewbie12]

I got some live rock from my brother to add to my tank....it has been in his sump, in the dark, for months. Today I noticed this white feathery stuff growing all over.....what is it? If it is bad what do I do to get rid of it? The pic only shows a small area coming from the side of the rock, but it was the best I could get. Thanks

 

[DeathclawRowe1]

It looks a bit like excess slime from corals or some form of algae. I'm not a expert but it could be some form of bacteria growing specially if the sump has been in the dark for a long period of time. Maybe look at the chemicals used to treat the sump and maybe it'll reveal some warning of growths idk

 

[saltwaternewbie12]

No corals in the tank it came from....was in total darkness and he said he has not seen any in the display tank.....when looking up close it looks like a carpeting of tiny feather duster heads, but no tube or body.....just the feather part......I was thinking maybe hydroids, but from what I find it seems they have tube like bodies too.....

 

[MINItron]

It's kind of hard to see, but it is entirely possible that it is a patch of tiny feather dusters. If they are embedded in the rock you may not see the body. Or they may blend in.