question about bristle worms

i have a monster bristleworm in my nano. i have lost just about every shrimp or crab i have put in this tank. i have two sand snails, 3 hermit crabs, a very small true percula clown, and one red scooter blenny. i always find empty shells but nothing else, when it comes to shrimp and emerald crabs for instance. my latest lost was a sexy shrimp (big sexy). i found his shell a few days ago and figured he was just hiding while his shell hardened. although, its been awhile and still no sign. my question is do any of you think that a bristle worm would do this, and if so he has to go. what do you think i could put in there that would get him if anything.

 

how big is he i guess its posibble

 

I got this type of hermit and it took care of all my big worms:

Dardanus pedunculatus

 

he is about 3 inches long about as big around as a pipe cleaner

 

the only problem with that hermit crab is i looks like it will eat anything else as well.

 

Try a worm trap.