Utricularia gibba. It's awful. It's actually carnivorus, not harmful to anything we can see, just micro organisms.
I've found just picking up as much as possible and then just taking it out when I see it works best, if you let it go unattended it will over run your tank.
RAOK CLUB #12
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"99% of the time, a fish tank with plants will fail. Once you start a dedicated planted tank with fish, then you begin to succeed." - Geniusdudekiran