In Reply to: That is why I don't think it is a feather duster worm posted by Elaine on September 23, 2007 at 18:09:07:

It sure looks like bristle type worm. I have not experience seeing them on any night dives, but my 150 gallons salt water fish tank that I do notice these worms are starting to multiplies. They only comes out at night to feed, and any disturbance they can go from 6" long to half and inch in seconds. Once a week after a night dive, I do go to my fish tank with a small light and pick some of these bristle worms of the rocks and glass. If one slip off the pliers they can swim blindingly very fast. Do not touch them with bare hands, their find bristles can easily penetrate skins.
The web site below shows very similar worms.

Bristleworm
Bristle worms live in the sand or within the live rock. ... Recently, most hobbyists have come to the conclusion that small bristle worms pose no threat to ...

www.reefcorner.com/SpecimenSheets/bristleworm.ht... - 9k - Worms.