Duckweed

Duckweed (Lemna minor) is the classic tiny floating plant, carpeting the surface with minute round leaves that multiply explosively. It's a nutrient-guzzling machine that shades the tank and provides cover for fry, and many fish nibble it happily. Fair warning: it grows so fast it's nearly impossible to fully remove once introduced, so add it with intention.

Care level: Easy · Placement: Floating · Lighting: Low-Medium · CO2: Not required · Growth rate: Fast · Propagation: budding (division)