I have one in my tank too. I think it resembles more of a slug than a worm. I have actually seen it releasing what appears to be eggs. It seems to do a great job keeping the rock clean but knocks over frags. I saw it stretched across my tank once from one rock to another and I swear that sucker was 8 inches long ... and I didn't see the end of it.

Found ID
 

Finally found ID on this thing. It's a chiton. Here's a link for more details.

http://www.poppe-images.com/images/s...tegory=chitons

So do I get prize for guessing right :razz:

If I had a prize to send you I would. Good guess.