ID This worm?

[RoyB]

Pictures are terrible. Have seen these a couple of times and not sure if it is friend or foe. Red worm about 1 inch long on glass.

 

[frisbee]

It looks like either a Cirratulid or Terebellid worm, both of which are harmless.

http://www.lionfishlair.com/hitchhiker.shtml