I have a Maxima clam that has several small feather dusters in hard calcium fortified tubes attached to the outer shell. One is protruding up toward the colorful flesh (sorry I don't know the correct name) and it appears that my clam is has dealt with it by splitting around it. It looks like a tear and it has me wondering if this if ok for the clam. I have picked off the feather duster but it keeps coming back. sorry no pics yet but I'll try to snap a few.

Are you sure they are feather dusters? I'd just cut them off if you feel they are bothering the clam.

It's possible that they are not feather dusters, but they are definitely some sort of hard tube growing on the back of the clam shell. I pick them off with my fingernail but they just seem to comeback.

it's called vermetid snail!!!
http://images.google.com/images?sourceid=n...ved=0CBIQsAQwAA

That's exactly what it is. Now to google if they are reef safe or pests.

On a clam they are very much pests.

In small numbers they are just harmless filter feeders. However, the goo they spit out irritates any nearby corals. And clams especially.

Trim the tubes down to knubs, then dab super glue over them... seal their doom.

Thanks for the help. That is exactly what I plan to do, and your right, they do expel a goo.