What is this?

[Dellis8781]

I have long brown looking strings coming out of the sand. It pulls in flake food when it lands on it and it wraps around anything that gets close enough like crabs or snails. Everything it grabs has no trouble getting away but I have no idea what it is. Any ideas?

 

[Poolman21]

Sounds like spaghetti worms. They are okay in small numbers but I have had them take over my tank and irritate my zoas.

 

[Dellis8781]

I looked up spaghetti worms and that is what it is.
Thanks for the info....