Need help ID creature in my tank.

[leonsaints]

I have a 30 gal tank and it's been running for 1 1/2 yr. When the lights out at night there are these sewing tread like creature coming out from my live rock, they are about half to 1 1/2 inch long and about a couple of dozens of them. Does anybody know what are these? and are they bad for my tank?

Any input/advice is very much appriciated.

 

[Meloco14]

Most likely spaghetti worms or some other type of worm. They are mostly harmless. They extend those very thing threads to capture food in the water.

 

[WRASSER]

Can you take a pic for everyone to see