What are these, budding LPS corals or what??

I have seen these things on my LPS corals (candy cane, frogspawn, and hammer) and I assumed they were buds on the main branches, but now I have seen a couple appearing on rocks and even on a snail shell. I thought maybe they were some type of algae, but then I felt them and they are hard and calcium like. Here's some pics:

 

Looks like mini feather dusters to me.

 

They look like vermetid snails to me.

 

Probably more likely, since there are no little feathers in any of the pics,
Duh! :frustrat:

 

Are they harmful? Do they move ever?

 

They are not harmful, but they can irritate corals if they grow large. You'll see during feeding time that they'll shoot out a web to catch food. If their webs start to cover corals, you can plug up their tubes with a drop of superglue gel.

 

Should I go ahead and do that now, or just leave them? Can I just break them off?

 

You can leave them, they are pretty cool. I'm not sure what breaking them off will do, if it will kill it or if it will just grow back.

 

I have two huge ones on the rock that my green star polyps are attached to. They're about as thick as a pencil. When they shoot their "web" out it's almost a foot long!

 

Vermatid snail growth is typically a sign of a well established tank with things going very well. I don't think they will have any adverse affects on your corals. I have them everywhere. I've had the webs drapped over just about every type of coral with out any issues on a daily basis. If fact, until I had to kill some redbugs on a large acro (the treatment kills all inverts), I had a colony of vermatids that were encrusted with Acro. They lived harmoniously for a year.

 

Ok cool. I've never seen any of these mysterious webs lol

 

Vermetid snails can grow to plague proportions. In the ocean, there's always a predator to eat them. In your tank, no predators to keep their population in check.

I don't know if I'd kill them, but if they start spreading rapidly, I'd start taking measures to slow them down. I like the superglue idea that Biff suggested, but you gotta figure if that kills them it's gonna cause a nitrate spike when they begin to die and rot

It is a sign of a healthy tank. Just don't let them begin to take over. I've read horror stories of people having to tear down the tank and start all over because of vermetid snails reproducing and turning into 10's of thousands in a reef. :shock:

 

I don't think killing a few of them will even make a blip in the nitrates. They are so small.

 

+1 on vermidtid snail. I personally cannot stand them.

 

No, but killing a couple hundred would.

 

I think everyone has a few here or there.I haven't witness them spreading to to plague proportions.

Btw,your live rock looks superb!

 

I wanna see a picture of that !

 

Here ya go (took it just now at breakfast):






Sorry they're not very good...

 

I've got tons of them, my rocks are almost spiky with them. They are all tiny. I had a huge one, tried breaking the tube, he fixed it within a couple of days.

 

Thanks, they are strange. Your pics are better than mine!!