whats produeing thread in tank

[demonsp]

I recieved a small piece of what i think is leather coral from Lfs which i recieved for free while purchising some snails.
ive noticed a thread like stuff which resembles half a feather. It seems to retract but not all of it, i also see a small yellowish spot on the coral by the thread, not sure if small yellowish thing is part of the coral or not it doesnt move the string looks cool also but still its all a mystery anyone seen this before. I foolishly forget to get a pic i will try tonight , cause this seems to happen after the light go out.

 

[Mrs.kbmdale]

Here are some visual identification sites that may help you figure it out, without a pic, I haven't got a clue....

http://melevsreef.com/id/
http://www.xtalworld.com/Aquarium/hitchfaq.htm

Hope you figure it out, Good Luck and Happy Reefing!
Brianna:rollface:

 

[2639]

Sounds like a feather duster.