ID please! Friend or foe?

[Millerman6401]

First time reefer, tank is around 8 months old. Just started noticing a few of these guys pop up and would like to see if i could get an ID.

They are in a rough/sandy textured tube. I cant see the base but it doesnt look like they curl, seem mainly straight. There are two clear antenna/apendages per tube that will wave around. They dont seem to produce any mucus/webbing so im thinking maybe not vermetid snails but i could be wrong.

The closest thing I came up with was some type of spaghetti worm? Still unclear if those are safe or not, if thats what it turns out to be.

 

[KrisReef]

Spaghetti is safe, I don’t know what you have - description sounds vermitid like. Worms that build sand tubes are generically safe,?but what they are?