Worm ID

[Coralguy8894]

I've seen a few of these worms hiding under my Ironman mushrooms. They come out here and there at night or during feeeding. What exactly are they and are they harmful?

 

[Gargoyle]

Bristle worms. Ugly but good clean up crew. Best not to touch them as they sting.

 

[El_Guapo13]

Bristleworm. Ugly? Yes. Disgusting? Yes. Hurt to touch with your hand? Yes. Bad for tank? No.