Found this on my clam, need ID and advise.

[srusso]

Doesn't seem to be effecting my clam but I was moving some stuff around in my tank and noticed this white stuff on my clam.

Flipped the clam around and took this picture. What do you think it is? Should I remove it?

 

[jeffreylesser]

Looks like the shell of some sort of fan worm. Harmless. If you are closely examining your clam you should be looking for these:

http://www.reefcentral.com/forums/showthread.php?s=&threadid=489644

 

[pskelton]

Looks like a vermetid snail. Does it send out a kind of spider web from its hole? I have had a few of these. As far as I can tell they are harmless but the spider web they send out to catch junk in the water can irritate corals around it. I kill them as I find them.

 

[srusso]

FYI it's bigger than a quarter.

Never seen anything come out of it, no nets or strings, doesn't have feathers. Little brown thing inside the two or three short alien like antennas.

 

[jeffreylesser]

Look up:

Spiral Tube Feather Dusters (Spirorbis spp.) on google images.

The shell looks like this to me. Feather dusters can lose their fans and essentially they are a worm. Could be something else. Still it is probably harmless.