bad or good

[sompa]

I just found these the other day and think they are hydroids. Can anyone tell me if that is what they are and if they are good or bad.

Thanks for the help

 

[Len]

They're prone to stinging corals and other benthic critters. I can't quite tell if it's hydroids or some cnidarian, but IMO it's best to rid them just to be safe (by removing the rock if possible).

 

[sompa]

How is the best way to get rid of them?

 

[Anonymous]

Remove the rock...its unclear in the pic..can you tell if the stalk looks "hard" (pardon the pun) or is it a soft stalk? if its hard it could be tube worms which are good...