Pretty Big Worm!!!! - Help identify

[Aquattro]

Wayne, mine came out for any meaty treat, as long as it was dark. It never fully left the rock and I could never catch it. Dr. Ron suggested cutting it's head off, as this type would not regenerate. I was not able to even do that. I spent hours trying to catch/kill this guy, but no luck.
However, if you can't verify that it is in fact eating things, it could be harmless. When I redid my tank, I found a 2 foot worm in the sandbed (it wasn't the same one) that never caused any issues I can think of.