Bristle worm invasion?

[joebob7]

I just went to turn off my lights in the 20 gallon and saw what look like baby bristly worms. They were about .5 inch, blue and were wriggling in the current, there were maybe 5 that I saw!
So did a momma bristle have some babies? Or are these even bristles?
any input would be greatly appreciated!

 

[joebob7]

I also fed my tank for the first time in a few weeks (it is all corals, no fish) so maybe they just came out of hiding for a shot at some plankton?