What type of organisim is this on my LR?

[spankey]

I have some LR that the other day my son and I noticed what appears to be stuff that is alive on it.. Some are in little tubes and when I mean little , they are very very small... When looking at the tube, you can see this organism creap its way out and open like a flower.. Then when a fish shoots by it like lightning speed shoots back down the tube... They are all over my LR.. Some don't even have tubes,,, Looks like they come right out of the pores of the rock...
Can anyone help me figure this out.. My son is totally amazed by them..
THanks
Spankey

 

[alexblanelayder]

a friend of mine said it's a type filter feeder don't worry they arn't bad because i have that too on my rocks

 

[therock0861]

As stated above the organisms are filter feeders and they are called tube worms and they will be on your filters and everything before long but there is nothing to worry about with them.

 

[brad524]

These are also known as feather dusters.
they are a good thing just another cleaner for the tank.
some get quite large and are very beautiful.

 

[alexblanelayder]

sorry but i would have to agree with the rock 0861 that they are tube worms. They don't grow as big as the feather dusters. thats what i thought they were.