Marimos are a low maintenance algae and very hardy. Some have even put them in salt water. Even a beginner can take care of one.


Can live in almost any container ranging from glass to an aquarium with fish. As long as it is submerged with water. 


Marimos live at the bottom of lakes in the wild, so they are fine under low lighting such as fluorescent lights and lamps. Don’t put it in direct sunlight or algae may start to grow on them. If this happens then pick it off.


Marimo living in aquariums need more care than those that live by themselves because they will get more dirty. If the plant becomes covered in too much dust and dirt then if won’t be able to receive light for photosynthesis. 

Glass bowl: every two weeks take the marimo out and run it under tap water. Make sure there is always enough water to cover the marimo. The marimo can be rotated so the bottom part gets some light.

Aquarium: every week take the marimo out and run it under tap water. Gently squeeze it but don’t squeeze too hard or it will float for several days until it has absorbed back it’s water.

Fun Facts:

a) If a marimo breaks in half it won’t die. You’ll just have two plants. Eventually it will grow into its famous ball shape or you can trim it into a ball with scissors.

b) It’s great for helping reduce ammonia, nitrates, and the absorption of other pollutants in the aquarium. It has a lot of surface area due to the thousands of hair follicles so a lot of beneficial bacteria can grow on it.

c) Shrimp and baby fish like to eat microscopic creatures off of it.

d) Background: they originally came from lakes in Japan but also come from lakes in Europe. Marimo are  actually a very special type of algae but it is very slow growing.

Find out how to buy a Marimo!