It's not Utricularia, is it?
Its a carnivorous plant that thrives on fish food and attaching itself to your plants. I have yet to completely remove mine, always seems to be some peice left. And its pretty harmless..Well that's just odd... is this a common aquarium plant? Should I be removing it or does it not matter? I guess there must have been some seeds/spores of it on the plants I bought.