I just freaked out. The lights are out in the tank and I look over and there's this 8" green worm swimming in my tank. WHAT IS THIS THING. It moves too fast to get a good shot.
Dunno for sure what it is, but when in doubt pull it out! There are lots of predatory worms out there. Sam used to have a eucinid worm that was like 4 feet long!
Oh it's out. You should see this thing move. Made me jumpy the rest of the night. The closest thing I found doing some research is some kind of parasite that lives in other invertebrates. Some turbo snail is having a much better day today.
In the first picture it has its tail curled exactly like some parsitic worms do. With out a close up of its head though I can't be sure. It reminds me of the picture in this link http://wiki.trin.org.au/Marine/WebHome