How to Care for Marimo Moss Balls

Marimo moss balls are surprisingly easy to care for. In this blog I will explain the basic care for them.

What are Marimo Moss Balls?

Marimo moss balls are actually a form of algae, not moss. Marimo balls can live for well over a century. They’re native to Japan and can live in fish aquariums (note that some fish have been known to devour theses). Marimos offer minimal filtration to your tank as well (though this is not significant and you still need a filter). Marimo balls are sometimes referred to as pets (I don’t understand why but you can consider your furry ball a pet!).

Where Should my Marimo live?

Marimo balls don’t like too much direct sunlight and will brown if getting too much. Choose a container that contains enough water to fully submerge your marimo. You should be able to remove the marimo from the bottle. You can put your marimo in a fish tank as well. If your worried about water spilling you can seal the container with a lid. Marimo balls don’t need oxygen so don’t worry!

Where can I buy Marimo Balls?

Marimo balls can be bought at your LFS (local fish store) or online. Personally, I bought my marimo balls from Amazon.

Note: If you want to place your marimo in an aquarium with other aquatics I recommend quarantining your marimos. Marimos have been infested with bugs before.

Some stores have been known to sell fake marimos. You can often differentiate between real and fake marimos by:

  1. Real marimos will usually float in water before sinking to the bottom of a tank.
  2. Real marimos will often have some brown blemishes (though a healthy one might not).
  3. Fake marimos might be perfectly round (real ones often are more spherical).

What Care does my Marimo Need?

Your marimo balls water should be changed every one or two weeks. Simply dump out the water and refill with tap or other water. If your marimo balls are in fish tanks do this during your routine water change. Give your marimo balls a light squeeze now. Try placing your marimo ball on a different side to simulate rounded growth.

Other Important Details

Two neons with a marimo.

Marimo balls can actually be kept out of water as long as they don’t completely dry out. Brown blemishes on your marimo usually indicates too much sunlight. Try moving your marimo to an area with less direct sunlight. I got four marimos about one and a half years ago, all with brown spots. Today, none of them have any brown spots.

Marimos balls will make an easy and fun addition to your tank. If you have any questions or comments feel free to post below.

2 thoughts on “How to Care for Marimo Moss Balls

Leave a Reply

Your email address will not be published. Required fields are marked *