Marimo Care

‘Marimo' are a species of green algae (Aegagropila linnaei) that are found in lakes in Japan and Northern Europe. Marimo are slow growers and require minimal care.

Low to medium light is great for these little guys.

Gently drain and refill with dechlorinated water when murky. To dechlorinate water: let water sit in an open container for a couple days before using. If aquarium looks excessively dirty, remove marimo and add very warm water to the container. Pop the cork on and give it a good shake. Drain, refill with dechlorinated water, and put the marimo back in.

If marimo themselves look dark or dirty, remove marimo from aquarium and gently squeeze out. Roll between your fingers to reshape and put back into aquarium with fresh water.

Marimo may float or sink, both are normal.