Why Is My Moss Ball Floating? Simple Science Explained

Why Is My Moss Ball Floating? Simple Science Explained

Have you ever seen your moss ball float up and wondered, "Why is my moss ball floating?" It's like uncovering a hidden trick in a game — unexpected and super cool. 

If your moss ball's floating act has you curious, you're in for some neat discoveries. 

We'll look at:

  • Their floating and sinking behavior.
  • Tips to monitor their buoyancy

Ready to learn more? Let's get into it. 

Now, Why Is My Moss Ball Floating?

Moss balls float due to a fascinating process called photosynthesis. During photosynthesis, moss balls absorb sunlight and convert it into energy, releasing tiny oxygen bubbles. 

These oxygen bubbles become trapped within the moss ball's structure, increasing its buoyancy and causing it to rise to the water's surface. 

When the process of photosynthesis stops, or the bubbles are released, the moss ball will sink back down to the bottom of the tank.

Study findings on how photosynthesis and biological clocks affect Marimo algae's floating ability.

Understanding this natural phenomenon provides insight into the health and behavior of moss balls in jars or nature. It showcases the relationship between plants and their environment, highlighting how simple biological processes can lead to fascinating behaviors in aquatic organisms.

It shows how plants react to their surroundings, demonstrating the effects of basic biological processes on aquatic organisms.

Take Note: The floating behavior of moss balls is a visible indicator of their well-being and vitality in aquatic ecosystems.

5 Tips for Monitoring Moss Ball Buoyancy

Here are some straightforward tips to help you manage and maintain your moss balls' buoyancy effectively.

1. Light Control

Place your moss jar in a location with indirect sunlight to prevent excessive light exposure, which can lead to overproduction of oxygen bubbles and floating. 

2. Regular Gently Squeezes

Periodically, gently squeeze your moss balls to release trapped air bubbles. This will help regulate their buoyancy and prevent prolonged floating.

3. Water Quality Maintenance

Maintaining optimal water conditions is crucial for your moss balls' health. While occasional floating is natural and not a cause for concern, regular water changes and careful monitoring of key parameters will help ensure your moss balls thrive in their environment.

  • pH Levels: The acidity or alkalinity of the water, measured by pH, should be maintained within a range of 6.5 to 7.5. This balance is essential for the well-being of moss balls, as it closely mimics their natural habitat. To help achieve and sustain this balance, consider using our Starter Kit, which includes everything you need to create the perfect environment for your moss balls, including our specially formulated boxed water. 
  • Temperature: Keep the water temperature ideal, between 68°F to 78°F (20°C to 25°C). This range provides a comfortable environment for moss balls to thrive and efficiently perform essential processes like photosynthesis.
  • Nutrient Levels: Check the water's nutrient levels, including nitrates, phosphates, and essential minerals, to maintain your Moss Ball's health and buoyancy. A proper nutrient balance is crucial. Although changes in these levels can affect buoyancy, attentive care ensures your Moss Ball remains healthy and vibrant.

Clean water promotes healthy moss balls and reduces the likelihood of them floating by ensuring that they can regulate their buoyancy effectively.

Also Read: Choosing the Best Water for Healthy Marimo Moss Balls

4. Avoid Physical Disturbances

Minimize disturbances to your nature, such as excessive water movement or unprotected handling of moss balls. Physical disruptions can release trapped air bubbles and disturb moss's ball placement.

5. Proper Handling

When moving or rearranging your jar or aquarium, carefully handle moss balls to avoid damaging their delicate structure. Rough handling can disrupt their buoyancy and cause floating issues.

To ensure your moss balls remain healthy and their buoyancy is not compromised, always handle them gently when moving or rearranging your jar or aquarium. To assist with this, our Moss Handler is designed for safe and precise handling, minimizing the risk of damage.


Whether your moss ball floats or sinks is less important than ensuring health and happiness. Proper care, guided by the tips we've shared, is crucial. Our Moss Care + Product is specifically designed to insure the well-being of your moss ball, reflecting our understanding that every aspect of nature, including moss balls, is significant. Caring well for your moss ball means loving and keeping it healthy, regardless of its position in the water.

Learn about moss balls and discover your ideal match at Moss Amigos, offering both essential care tips and a selection of beautiful options. 


Ramirez, D. C., De Fraine, T. S., Griffiths, O. G., & Dodd, A. N. (2018c). Photosynthesis and circadian rhythms regulate the buoyancy of marimo lake balls. Current Biology28(16), R869–R870. https://doi.org/10.1016/j.cub.2018.07.027


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