I was browsing through my tank tonight when I noticed something odd... the best way to describe it is it looks like a clear straw underneath a ledge on a rock, the bigger type, not the cocktail type. When I looked closely, the end of it kind of closed up. Nothing is sticking out the end of it and nothing "hides" back inside when you go near, so I don't believe it's a worm. I've checked a couple of the ID sites but have come up empty. Anyone have any ideas about this? Friend or foe? How to get rid of it if necessary? I'm leaving tomorrow for a few days so I'd like to take care of it ASAP if I need to. Thanks.