Lemna minor

Lemna minor is one of the most widely distributed plants on Earth, found floating in still and slow-moving freshwater on every inhabited continent. Each frond consists of a single flat, oval body 2–5 mm across with a single root hair. Its extraordinary growth rate under good light means it can double its biomass in a matter of days, providing an essentially unlimited live food supply for goldfish, koi, plecos, and many tropical species, while simultaneously stripping nitrate and phosphate from the water.

Light: Low to medium surface light sufficient; grows fastest under bright direct light. CO2: Not required; absorbs nutrients directly from the water column. Planting: Simply introduce a small portion to the water surface; no other action needed. Maintenance: Thin the colony regularly to prevent total surface coverage and light deprivation for submerged plants. Note: Can become invasive — once introduced it is very difficult to fully remove; manage proactively.