Common Duckweed

[Eclecticoldsod]

why does everyone knock it? It grows well in my shrimp tank, and every couple of days I take out a handful for my goldfish and community tanks. It never lasts more than a few minutes – a nice, free, always available sauce of food for all the veggie lovers. No danger of taking over these tanks, it doesn't last long enough!

 

[aaronnorth]

Because it grows to fast and blocks out the light, it is not as controllable as other floating plants e.g. water lettuce