Is this good or bad

[Darkwater]

I bought 3 cerith snails from my lfs. 2 were empty shells, the other ended up being a hermit crab. The pic is of a red worm of which mutliple came as hitchikers. I need to know what type it is and if its good or bad. Any help is appreciated.

 

[Darkwater]

Same one better picture.

 

[Crabs McJones]

Spaghetti worm

 

[Darkwater]

Are sphegetti worms good or bad, this is my first saltwater tank in 39 years, i was 12 when i had one previously, so basically brand new again. Thank you for your help.

 

[Crabs McJones]

They're good. They are detritus eaters.