Aquarium moss balls are one of the best things you can add to your tank. Being popular with both beginners and more advanced aquarists, there is a huge range of benefits that you can get for your existing or brand new tank!
What are the benefits of aquarium moss balls?
- They Absorb Nitrates
- Moss Balls Provide Oxygen
- Moss Balls Do Not Add Dead Matter
- They Are Almost Maintenance Free
- They Are Very Resilient
- They Discourage Excess Algae Growth
- Moss Balls Keep Healthy Bacteria
- They Handle Salt Well
- They Do Not Bring Foreign Items into Your Tank
- Moss Balls Do Not Need to Be Anchored
- The Balls Are Slow Growing
- Moss Balls Are Easy to Keep Clean
- They Can Also Be Used for Decorative Purposes
- Can Easily Live on The Minimum Requirement of Sunlight
- Changes to Moss Balls Can Show Problems
- They Are Great for Beginners
- Some Creatures Enjoy Moss Balls
Since they are such an easy addition to your aquarium, let’s talk more about what aquarium moss balls are, and what the benefits to see exactly what aquarium moss balls can do for you!
What Are the Benefits of Aquarium Moss Balls?
Aquarium moss balls are the easiest underwater plant that you can use. Perfect for beginners and seasoned aquarium owners alike. Since they require almost no maintenance and are basically indestructible, it is a companion for your tank that you don’t have to think about.
In addition to them being easy to maintain, they provide a ton of benefits to the tank as well. From cleaning out toxins to create a better environment for the fish, to acting as toys and places for fishes to hide, they create a fun environment for them as well.
Aquarium moss balls are easily accessible and affordable, which makes them perfect for those who may just be starting out. In addition to being used as a companion to fish and creatures in tanks, some people even use them as pets!
So, let’s talk about what aquarium moss balls actually are!
What Are Aquarium Moss Balls?
Also known as Marimo or Cladophora balls, these originate in the northern hemisphere.
Moss balls get their name from the way they look, but they are actually just dense algae and are not a moss at all.
They are naturally found in different lakes located in Iceland, Japan, and Scotland, just to name a few! They naturally form in cooler water that is slightly brackish. They often get their shape from rolling in water, such as lakes and rivers.
Here is a breakdown of the seventeen benefits that aquarium moss balls can provide your aquarium, and exactly what each of them mean!
1. They Absorb Nitrates
Nitrate is a combination of leftover food, fish waste, and dead plant matter. Combined, all of these create ammonia. Ammonia is then turned into nitrite and then nitrate after coming into contact with bacteria that exists in the biofilter in your aquarium. While nitrate is the least toxic to your fish, if left untreated, it can become a problem.
Aquarium moss balls actually reduce the amount of nitrates in your tank. Nitrates actually help them grow and live, so they are essentially sucking them out of your tank water. This keeps the water a little cleaner, but regular cleaning is still the best way to maintain a clean tank.
Moss balls can also clean out phosphates and other forms of organic waste that may be hiding in your aquarium. They play the role of both passive and active defenses against nitrate levels that can cause trouble for your fish.
2. Moss Balls Provide Oxygen
Fish need oxygen to breathe, and all underwater plants are a great way of providing that. Aquarium moss balls absorb the carbon dioxide released into the water by fish, and then they replace it with oxygen. If you’ve heard of photosynthesis in plants, then this is exactly the same process!
It is not a high level of oxygen, but it is enough to keep a healthy tank for your fish. Depending on the size of your tank you may need more moss balls to actually make a difference. For some owners, this is a better alternative to noisy air rocks, which are commonly used.
3. Moss Balls Do Not Add Dead Matter
One of the best benefits of moss balls for your aquarium is they do not produce any dead matter that is added to your aquarium. Since they are a form of algae, you won’t have to worry about them shedding or any dead leaves falling off.
Goldfish tend to damage the moss balls, as well as getting caught in filters. Other fish and tank creatures don’t bother them, so you won’t have to worry about that! As long as you keep your moss balls green and spherical, you’ll have no issues!
4. They Are Almost Maintenance Free
The reason aquarium moss balls are so popular is that they are the easiest underwater plant to maintain! Other than trimming areas off that did not get enough light. You simply need to just rinse them out whenever you are cleaning your tank.
You can also take them out once a week to make sure they are in the best shape they can be! Your moss balls prefer cold water. This is apparent based on where they are found in Iceland, Scotland, and Japan. If you have to, you can move your aquarium to a cooler area to keep the temperature down.
Aquarium moss balls do not require any special lights, filters, foods, or carbon dioxide system to stay alive. You can use these in almost any tank that you already have.
5. They Are Very Resilient
Aquarium moss balls are really hard to kill! Other than letting them completely dry out, the last thing you need to worry about is your moss ball dying. Using chlorinated water,
If you take the necessary steps to take care of your tank, then your moss ball can live over a century!
Goldfish are really the only fish that tend to bother them. There are a few signs that your moss ball might need a little attention, but we will to that a few benefits down!
6. They Discourage Excess Algae Growth
Aquarium moss balls actually eat the same nutrients as algae that you don’t want living in your tank. This makes it pretty hard for any excess algae to grow simply based on the lack of food available for them.
Something to remember is that it is important to apply the number of moss balls inside of your aquarium. If you have a large aquarium, you will need to have more moss balls to combat the growth of unwanted algae.
This is another benefit that really depends on the size of your tank. The bigger the tank, the more moss balls you’ll need.
7. Moss Balls Keep Healthy Bacteria
Moss balls have their own beneficial bacteria that helps that can seriously benefit your tank cycles. Since they are a living, they act as another filter in addition to the filter you already have for your aquarium. They can really be a help when maturing a new tank.
It is not recommended to place a moss ball in the filter since it can damage the moss ball, but they are beneficial for the nitrogen cycle of your tank.
8. They Handle Salt Well
Many of the popular plants for aquariums don’t do well if they come in contact with salt. Moss balls are typically found in brackish water, so they are one of the best plants for your tank. People often use salt to treat injuries or parasites in their tank. Salt can also help moss balls if they are turning brown as well!
If you want to use moss balls, make sure you keep an eye on your salinity levels. You can purchase a hydrometer at your local pet store in order to monitor these!
9. They Do Not Bring Foreign Items into Your Tank
No matter how careful you are, buying new things for your tank may bring in some unwanted guests. These can range from small creatures all the way to parasites that you won’t even know are there.
Moss balls often come in their own cups, so they are not as exposed to foreign bodies as other items are. This means that you can safely place them in your tank without worrying about them, causing more damage.
10.Moss Balls Do Not Need to Be Anchored
If you have ever planted anything in an aquarium, then you know that it is not fun. There are a lot of factors you need to know about your tank in order to find plants that are going to not only survive, but thrive in your tank.
Moss balls require no anchoring or planting to anything. You can throw them in the tank, and they are good to go. They even float and sink on their own due to the natural gasses that it produces inside of it.
You will often see moss balls sink at night and float during the day. This is a natural process that is similar to how plants appear to be sleeping when they are in and out of the sun.
11.The Balls Are Slow Growing
The aquarium balls are very slow growing which is great! Growing only about a few millimeters a year, you may not even notice it! They are not going to regenerate and take over your tank, nor are they going to grow huge and become a nuisance.
While they can get up to the size of a bowling ball in lakes, that behavior has not been witnessed in a tank, so have no fear!
You can propagate moss balls by removing the water and cutting them in half or thirds. If you’re worried about the spherical shape, then make sure to keep rotating your balls as they grow and evolve.
12.Moss Balls Are Easy to Keep Clean
Although moss balls are low maintenance, they do need occasional cleaning. If your moss balls are living with other fish or creatures, then you’re going to want to clean them when you clean your tank. Since they act as a sort of sponge for all of the things you don’t want, they can get pretty dirty.
Squeeze your moss balls in a container of clean water a few times. Since this is made of algae, you’ll want to make sure you keep a firm grip, or it could fall apart. If this happens, just roll and mold it in your hands to get it back together.
13.They Can Also Be Used for Decorative Purposes
In addition to all of the benefits we have discussed, they actually look great in your aquarium tank as well! Since they are a natural item, they do not stand out in your tank, and they are great for keeping your tank environment on the more natural side!
Since they have such a unique shape, they add a different level of interest when paired with things such as wood and rocks that are often used.
You can find moss balls in a variety of sizes for your tank. For smaller tanks, smaller moss balls would fit the scale better While they don’t get enormous in tanks, larger moss balls are a great investment for those who are serious about their aquarium.
14.Changes to Moss Balls Can Show Problems
Since your moss balls are living things, they can tell you when they need something. If your ball ends up too brown, then that means they are getting too much direct sunlight. You can fix this by moving your ball to another area within the tank.
If black spots appear on your moss ball, then you know that is a sign of decay, and you can trim that area away. You can resolve this issue by using cold water and aquarium salt.
If you notice your moss ball losing its’ spherical shape, then that is a sign that it needs to be rotated. Your moss ball will regain its shape and keep protecting your tank.
15.They Are Great for Beginners
Since the maintenance of aquarium moss balls is so easy, they are great for people who are just starting out with an aquarium. You can simply rinse them in your aquarium water and toss them in. These make the perfect item for tanks that are more on the simple side or may be low-tech.
Since many people who are starting out are on a budget, aquarium moss balls are easily accessible and very affordable. Just make sure you’re getting authentic moss balls and not replicas in order to get the full benefits!
16.Some Creatures Enjoy Moss Balls
A lot of freshwater aquarium shrimp are fans of moss balls. Some food gets caught on the surface of the ball, and the shrimp can enjoy a snack. The moss ball itself is only seen as a food source to goldfish, so they are relatively safe!
Snails also enjoy scouring the balls for food, but they do not damage the moss ball leading to dead matter floating in the tank. Betta fish enjoy playing with these, and other fish enjoy using them to hide near.
How Many Moss Balls Do You Need for Your Tank?
Like mentioned earlier, the size of your tank is relative to how many moss balls you’ll need to reap the benefits that they offer. For gallon tanks, it is recommended to have one to three balls. Tanks over five gallons need between five and eight balls that are at least 2.5 inches.
A ten-gallon tank can handle between eight and thirteen balls. The next level up, a twenty-gallon take, is perfect for about twenty different moss balls. This is all depending on the care you put into your tank and how much moss you think is appealing.
Where Do You Get Aquarium Moss Balls?
Moss balls are relatively easy to find. Major pet retailers often stock them in the same area as betta fish. If you’re a city has an aquatic store then this is also a great place to find them. Make sure that the moss balls are bright green, which represents good health.
You’ll also want to be aware that some retailers stock java moss or similar replicas. Typically, if it looks too cheap, then you are best to avoid it. Another thing to look out for is to see if the balls have been quarantined This will make sure they are free and clear from anything potentially harmful.
You can also buy moss balls online. If you purchase them online, make sure you’re getting a real one. There are fake ones that have none of the benefits of the others. You can identify a fake moss ball by the unusually perfect shape, as well as the texture of the ball.

Hi, my name is Adam and I’m an aquarium enthusiast! I didn’t discover the joys of being an ‘aquarium fanatic’ (as some of my friends call me!) until I was in my 20’s. When I first started out I found it difficult to find all the information I needed so I started this website to compile all the useful information I can think of. Enjoy!
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