Cant ID these worms?

[Kronk]

I have noticed these creatures in my reef from the start mostly at night they are small maybe 1/4" max diameter and have 7 or 8 tentacles. I have seen one puking out a collonista snail shell once so I think they may be predatory but my reef is packed with pods so it may have just been a fluke. They are in my rocks and sand and dont ever seem to move they just kind of sit there with there tentacles extended all night. My concern is that the closest thing i can ID them to is a Euncid worm!!! but like i said they don't seem to move and nothing in the reef shows signs of being chewed on... so i am at a loss as to what they may be, any ideas?

Thanks,
Ken