what the heck??
 

is this thing? It looks like a mini earth worm, it's about 1cm in length. It's sitting on a bag of chemipure that I pulled out of my filter...

http://invigor.sasktelwebsite.net/worm.jpg

Yikes! Haven't a clue what it is. Here's an article on worms that might be of assistance in IDing your worm:

http://reefkeeping.com/issues/2003-04/rs/index.htm