HELP NEEDED: Worms in tank

I have a 20 gal and 55 gal. Last night I noticed these little hairs floating around, and when I looked closer I saw they were crawling up the sides of both tanks and were all throughout the rocks. When I get home from work I'm going to take a water sample and have it lokked at, but while I'm here, I was wondering if anyone knew what these were called? I've heard about it before, how these little worms lay eggs in the rock and then travel around the tank. Usually they come from another infected tank (my bf got some feeders from a store we've never been to before, other than that nothing has been introduced to my tanks in months). I'm really disgusted by these things, and any help or direction would be greatly appreciated. I've never had anything infect my tanks before. Thanks!!

Thats good to know. I don't overfeed, and my bottom feeders clean up any excess thats left over. So, it sounds like they're not parasitic. Is there anything I can do to get rid of them, short of starving the tanks to kill them off? Theres a great store here in Phoenix I can take a water sample to and have them look at it. I just don't even want to get near that water, those things make me sick.

FYI: I did a huge search on nematodes and planaria and other nasty little things, and I found some pics of nematodes, which are exactly whats in my tank. It said to have my fish fast for 3 days and they should die out, and they won't harm my fish. They sure are nasty, though...