I was looking at my tank when all of a sudden I notice this worm-like creature. It looked like an earthworm, but it was white. It was on a small rock on top, so I quickly took the rock out that it was on. When I did, it shriveled up to a tiny little thing, then went into a hole in the rock. I have had this rock since I got the tank, and I havent added anything new other than 10 snails today. Does anyone have any idea what this could be, and is it dangerous? If I see it again, i'll try and take a picture.
Thanks for the help!