4 in red worm

I have this long red worm in one of my tanks. It is bright red and slides across the glass like a snail. It is slightly fatter than a good sized black worm. Any ideas what this might be?
It also burrows in the substrate.

Does it look like this leech? Image: http://img.photobuck...imiru/014-3.jpg
It moves side to side like this when it's not scooting around on its butt. Movement:



The leech species above never attacked me or my fish, so I figure it's a detrivore. But I made them extinct anyway, because they were creepy looking.

Edited by EricaWieser, 10 November 2011 - 11:34 AM.

"glides like a snail" suggests a flatworm, prob not a leech.
Erica's monster leech was most likely preying on worms and/or snails.

"glides like a snail" suggests a flatworm, prob not a leech.
Erica's monster leech was most likely preying on worms and/or snails.

*nods* True.

Those leeches initially showed up in the tank back when there were just snails in it. Then when I added blackworms they ate them, too. They lay dark oval eggs, which look kind of like a shark's purse, on hard things like PVC pipe and shells. The young burrow under the ground and once they get about oh, four five six inches, you can see the burrows they make kind of like Bugs Bunny burrows, compressing the earth up as the leech travels. Without predatory fish around the large adult leeches come above ground and wiggle. The leech you see in the video above was in a tank where the only fish was Elassoma gilberti, four inches shorter than the leech and zero threat to it.

If you see your worm gliding like a snail then yeah, it's not a leech. But if it reaches its head out questing, then picks up its butt and places it down, well... that's a leech. But it doesn't mean anything bad, necessarily. My leeches never attacked me or my fish. They just ate the snails and the blackworms. I happened to like my blackworms though (they were there as food for the fish), so I exterminated the leeches.

It glides across the glass in a straight line. Definitely not a leech. Very thin body like a blackworm, but bigger.

It glides across the glass in a straight line. Definitely not a leech. Very thin body like a blackworm, but bigger.

Can you take a picture and post it here?