What is growing on my rock?

[devonmessick]

Hey! I am only about 6 months into my first salt water tank. I noticed something growing on one of my rocks. I feel like it came out of no where. It is a white worm like thing with something growing out the end of it. Is this something I should be worried about? I have no added anything new into my tank in over 3 months except for using live water when I do water changes every other week. I have attached a photo. It looks like it has popped up in a few different places. I have circled what I am talking about.

 

Thanks in advance!!!

Devon

 

[Tamberav]

Looks like a feather duster tube, good guys.

 

That is some nice looking rock

[lakshwadeep]

Feather duster worms, in this case forming hard tubes.