Single Marimo Moss Ball | Unique Living Algae Sphere | Low-Maintenance Aquatic Plant

A Living Marimo Moss Ball, Hand-Selected for You 🌿

The Marimo moss ball is a rare, naturally spherical form of green algae (Aegagropila linnaei) that gathers into soft, rounded colonies in cold freshwater lakes. Each one we send is a single living sphere, roughly an inch across, with a deep velvety-green surface that catches the light like fine moss. No two are identical, and that gentle, hand-formed character is part of their charm.

Beyond its quiet beauty, a Marimo is a working part of an aquatic ecosystem. Through photosynthesis it draws in nitrates and releases oxygen, gently supporting cleaner, clearer water in an aquarium or jar. In water it rocks and rolls with the slightest current, the same slow motion it makes on a lake bed, which is why so many keepers think of it as a calm little plant pet rather than simple decor.

Caring for a Marimo asks very little of you. It is happy in cool, clean water (about 60 to 78°F) and low to medium indirect light, with a water change every week or two. Give it a gentle roll now and then to keep its round shape, and keep it out of direct sun to protect that rich green color. For a full walkthrough, see our Marimo Moss Ball Set-Up Guide and our Care Guide.

Marimo are cold-water freshwater algae that thrive in clean, cool, slow-moving water, the conditions they evolved in. We partner with a vetted U.S. grower who specializes in exactly those conditions, cultivating and hand-shaping each sphere in clean freshwater to the same standard of care that defines our own Colorado farm. Every sphere is hand-selected and inspected before it ships, and backed by the same 100% money-back guarantee as everything we carry. If you are weighing your options, our guide on Marimo vs other aquatic plants can help you choose.

Product Details

Marimo Moss Ball FAQs

Is this a real, living Marimo moss ball?

Yes. Every sphere we ship is a real, living Marimo (Aegagropila linnaei), a naturally spherical green algae, not a synthetic or pressed imitation. We hand-select each one for a dense, healthy, velvety surface and a rounded shape before it leaves us.

Where does your Marimo come from?

Marimo thrive in cool, clean, slow-moving freshwater, the conditions they evolved in. We partner with a vetted U.S. grower who specializes in exactly those conditions and cultivates each sphere in clean freshwater, held to the same standard of care that defines our own Colorado farm.

Do I need a tank, filter, or special equipment to keep one?

Not at all, and that is part of the charm. A Marimo is happy in a simple jar or bowl of cool, clean water with low to medium indirect light. Change the water every week or two and gently roll the ball now and then to keep its round shape. Our Marimo Moss Ball Care Guide walks you through every step.

Is it safe around my fish, pets, and children?

Yes. Marimo are non-toxic and a favorite in community tanks with fish, shrimp, and snails. We do suggest keeping the ball in a stable bowl or closed aquarium and supervising small children and curious pets, since the whole sphere could be a choking hazard if swallowed.