Please help me ID, this is on a rock covered with hairy mushrooms

[jim2766]

This always seems to have a silk like string comming out of it, and over time it seems to get larger. It does not seem to move. The base looks like it is coiled. I have had this for awhile, but had not have time to ask for help getting identification. All assistance is greatly appreciated!!

 

[meowzer]

It's a vermited snail....beneficial to the tank..it's a filter feeder
The base is kinda hard, and the worm comes from in it

 

[gregzbobo]

I've heard that sometimes the mucous net it puts out to catch food can irritate nearby corals, if you think thats happening, you can superglue it shut or jam a dab of epoxy over its opening. Otherwise pretty harmless.

 

[renogaw]

shouldn't hurt the hairy shrooms, those things are tough enough

 

[deathtopoopie]

Thanks, I had one of those too, and you guys helped me out also.

 

[mr.clownfish]

i have a bunch of them. the stringy stuff is annoying but i like them cause they help clean up a bit

 

[fretfreak13]

I have lots and they reproduce fast, IMO. I didn't mind at first, but when their webs starting irratating my Zoas I crushed their shells with tweezers out of revenge. Cran suggusted I do that awhile back and I thought it was mean, but I know what she means now. lol