Hydroids...?

[sapphireminer]

Based on similar forum photos, assuming these critters at the tips of my favia are hydroids. They move with the flow with tentacles at the end.

1. Do you think they are hydroids as well?
2. How harmful are they? Anyone have any examples of the harm they have caused to their corals?
3. Besides drastic measures (boiling rock) and tweezing them off, are there any ways to get rid of them if they cause harm?

This is also a new tank (1 month old), so I don't want to do anything drastic if this is just par for the course for a new tank.

 

[Labridaedicted]

Yeah, sure looks like them. They will sting and irritate any coral they touch. Quick and dirty fix to get rid of them since it's a small patch is to just cover them with gel superglue like you'd use to attach frags anyways.