What is this and is it dangerous??

[jake22]

one of pieces of live rock has tons of there worm like things all over it. It is currently in my sea horse tank. Will these thing pose any threat to anything i put in my tank.

 

[jake22]

anyone??

 

[s.a. boy]

I looks like a small fan worm to me have out ever seen something come out of it?

 

[nacl-h2o]

It's a harmless filter feeder. Vermetid snail

 

[bang guy]

Vermetid snails drag their two streamers across rocks and substrate. They trap some food particles from the water column but they also capture and eat a lot of detritus. On the grand scheme of things they are probably a good guy in the cleanup crew. Sometimes that can irritate a coral as the threads drag across it but I've never seen any long-term detrimental effects.