Small white cottony tubes?

[jdesantis]

Ok, I have been looking through posts now for about an hour and not finding exactly what I am looking for, so...

I just noticed yesterday evening, some little white cottony looking tubes that are appearing on my live rock, and a few on the glass. I am thinking that they might be SPIRORBID WORMS but not sure, this was the closest thing I could find to what mine look like. See the pic, hopefully someone can confirm, or state otherwise. Thanks in advace. I have had the tank setup for about 9 months with no major problems, and everything seems happy and healthy.

Check the image that is on my profile, I could not get it to attach to the post. Thanks

 

[roka64]

I moved this to the ID section.
They look like harmless sponges. They are good filter feeders.

 

[jdesantis]

Great, thanks, How big can i expect something like these to get? There are quite a few in the tank, on the rocks, is this something that will overtake everything?

 

[roka64]

No, they come and go as their food source does. They typically don't get that big.