What is this 5'' worm? It's not a bristle worm.

[TessGlo]

Hi all,
Found this freaky thing when I removed the sand from my frag tank. It has no legs on the bottom. It's almost transparent, you can see it's insides moving. Part of it retracts (see photos). My LFS said its a coral eater but was not sure what it is called. Not surprising, but I will note that it or it's eggs made it through multiple dips because this tank started w/ dry rock and all corals were dipped. I never noticed my corals being bothered.

 

[DSC reef]

Looks like a peanut worm. If it is it's not harmful. @Lovemyreef2015 @KJ

 

[reef lover]

Yup peanut worm

 

[Mikedawg]

Might find this interesting: https://reefbuilders.com/2015/05/11/peanut-worms-reef-aquarium/

 

[KJ]

Peanut worm

 

[TessGlo]

Thank you all, very helpful!!