I've been having these strange stringy plants grow in my 10gallon planted aquarium for a couple of months, and I thought they might be some kind of flower stem or something as they had little almost flower-like nodes on them, but turns out (after some research) they are bladderworts! How cool is that? I've had most of the plants in that tank for years, and the recent additions came for a freind (who doesn't have any bladderworts) so I can only assume the bladderworts came from seeds or spoors in the soil I recently placed underneath the substrate. There are about six of them ranging in size from one or two inches up to about six inches. They are neat, but very, very small and gangly-looking. I hope they get enough to eat!