Tubeworms?

[Aquatics UK]

Hi,

I have had my reef tank set up for around 6 months and the live rock came from my last reef tank so I have had it for around 4 years.

There have always been a few of what I assumed were small tubeworms (although there doesnt appear to be anything coming out of the end) on the rock but lately the poulation has exploded. There are now thousands of them coverng the live rock and even my turbo snails are covered in them. (photos below)

A few questions if someone would be kind enough to help me out:-

Are they tubeworms?

Are they harmfull? Should I be trying to remove them?

I have attached a photo of what I think is an egg sack. am I correct? If so, would removing these (there are 6 or 7 of them) reduce the amount of tubeworms.

Thanks

Dave.

http://reefcentral.com/gallery/data/500/85366worms.JPG

http://reefcentral.com/gallery/data/500/85366snail.JPG

http://reefcentral.com/gallery/data/500/85366egg_sack.JPG

[divewsharks]

Possibly a Vermetid. Does it look like this, close up?
http://www.reefs.org/hhfaq/worms/photoalbum_photo_view?b_start=7

[Aquatics UK]

I havent seen anything like that coming out of the tubes but they are very small so its difficult to see.

[Sugar Magnolia]

Those are vermetid snails. They send out a very thing strand of mucousy looking stuff that traps anything floating past. Typically mine come out whenever I do a water change and or anything that stirs up any extra flow to the tank. They do tend to reproduce very quickly.

Here's another article to read: http://reefkeeping.com/issues/2005-01/rs/index.php

[Aquatics UK]

Thanks for the ID :-)

Are they harmfull?

And does anyone know what the "egg sacks" are?

[Reef'in Colorado]

Vermetid snails can irritate surrounding corals with the mucous like web they send out, but otherwise harmless. The last photo ou posted looks like a sponge to me...

[GoBigOrGoHome]

the egg sacs are definitely sponges