Unidentified critter. Help

[hardimanm]

The picture i am adding is horrible but maybe my explaination of it will help someone ID it. I wish it was a better pic but the thing is kinda on the rear of a rock with another rock above it. I noticed it a few weeks ago and it has never moved

the thing is a crimson red color and circular. It appear to be attached to the live rock and is in and is receiving full light. It appears to have 2 antenna and some form of an oral disc.

I watched it for a while today and it reminds me of some sessile form of a snail. I watched it long enough to see it "poop". This too looked like snail "poop". It also appear the antenna and "mouth" is coming out near an overhanging of what ever is encircling the thing.

Does anyone have any idea what this thing is? And if it is some sort of "snail" what is it eating? It is not eating into the rock is it?

 

[mstwell]

Tube worm. Harmless filter feeder who filters fine particles from you water. You can find more information at:
reefkeeping.com/issues/2003-05/rs/index.php
Look at the Family Spirorbidae.
Hope this helps.

 

[Tomoko Schum]

Your description seems to match a vermetid snail more closely. Take a look at this article by Dr. Shimek.

 

[hardimanm]

Tomoko you seem to be right. Now the only question is wheter to remove the critter or not. So what would the best thing to do? It appears to be growing quite quick. Since i last posted this question it has added about 1/2 inch of spiraled shell.

If this was your tank...would you remove the critter or just leave it be?

Thanks
Michael

 

[Tomoko Schum]

I don't mind them as long as they don't bother their neighbors. They multiply fast, though.

 

[wpecoul]

If the mucous web is likely to irritate any neighbors, I'd get rid of it. The larger ones can get messy at times.

 

[JR's Reef]

I had some that completely took over my tank I ended up taking all the rock out and having to dry them and bleach them.
I would sugest getting rid of it by supergluing the hole or getting some of the puddy stuff and sealing its exit hole closed.