How Many Bio Balls Per Gallon Of Water? Your Answers Here!

Last Updated on September 8, 2024 by Sara Rose

A bio ball is a modern tool created to filter your tank water. If you want to use bio balls, you will need to know the answer to the question: How many bio balls per gallon of water?  

We have written this detailed article to give you everything you need to know. 

Every tank needs a filter. A filter is crucial in keeping your tank water clean and ecosystem balanced. Water passes through the filter and catches debris from your tank.   The clean water then re-enters your tank to make a happy ecosystem for your fish! 

There are many different options for filters, and one of them is using a biological filter. A biological filter uses natural principles to filter the water.  

It is the most sustainable filtration method. This is one of the reasons we recommend it.  

One type of biological filter is called the bio ball. A bio ball is a small ball, often made of plastic, that contains natural bacterias which clean your water. You place the balls in your filter system.  

In order to use bio balls properly, you need to know: How many bio balls per gallon of water? Keep reading now to find all the answers! 

What Are Bio Balls?

We mentioned a brief description of bio balls in the introduction, but now let’s go into more details about how they actually work. These plastic balls contain many different pegs.  

The pegs increase the surface area of the ball, which increases opportunities for bacterias to live. These beneficial bacterias eat the debris from your fish tank.  

The aerodynamic shape of the balls allows them not to be clogged quickly. This is very convenient because it means you do not have to clean your filter often.  

If you want to clean your bio balls, simply dip them in another container of water and allow for all the debris to build up to fall off. This is far easier than cleaning a traditional filter.

Water moves over and around the bio balls, which helps create CO2 and oxygen. This reaction fuels the bacteria to change harmful nitrates into a usable form that can enter your tank.  

Again, the shape of a bio ball is very convenient because it allows air and water to move through the system with ease. So, you do not have to worry about any blockages in the flow of your system. Since bio-balls are made out of plastic, they will not retain any water.  

Another reason people choose to use bio balls is because they are very convenient. You simply drop them in your filter.  

There are different companies that manufacture bio balls, and each one has a unique design. On average, they are about 1.5 inches in diameter.  

The exact type of plastic they are made out of is HDPE, high-density polypropylene. This is one of the strongest plastics out there. So, you can use bio-balls for a very long time. 

bio balls for fish tank

How To Use Bio-Balls For Fish Tank

Even though the balls are only 1.5 inches in diameter, their surface area is more than 21 inches! This increased surface area is what makes them so unique.  

It is a very useful tool, especially for large-scale projects. In fact, bio balls are often found in big koi ponds, fish farms, and even in wastewater treatment facilities.

If you want to use them in a fish tank, it is also possible. All you need to do is drop them into your fish tank!  

At first, the bio balls will float to the surface of your fish tank. But eventually, as the beneficial bacterias colonize on the surface of the bio balls, they will sink to the bottom of your tank to work. 

When harmful ammonia and nitrates are produced in your tank, the beneficial bacterias will consume and decompose it. As long as you do not clean the bio balls, these bacterias will continue to exist and grow.  

You can even take a few bio balls from one tank and move it into another to give it a head start! Hopefully, you can see how easy and convenient these are to use.  

However, they are not a perfect solution. No matter what, you have to continue to monitor the ammonia and nitrate levels of your tank to ensure your fish will not be in danger.

You can purchase water-soluble test kits from any aquarium store. Take measurements on a weekly or bi-weekly basis to understand the ecosystem of your tank.  

Another reason bio-balls aren’t an end-all solution for water filtration is because you need a lot of them to be effective.  

This gets us to the very important question: how many bio balls per gallon of water?

So, How Many Bio Balls Per Gallon Of Freshwater?

Unfortunately, if you want to have a 100% efficacy rate of absorbing harmful bacterias, you need to use a very high quantity of bio balls. This is why bio-balls are good as an in-tank supplement to filtration but cannot be the only thing you do.  

It is recommended that you use 100 balls per 1 gallon of water in your tank! You can see that is a lot, especially if you have a small tank. For example, if you have a 10-gallon tank, you would need 1,000, 1.5- inch balls!  

This means that there will not be enough room for your plants and fish. It is for this reason that we only recommend using bio balls on large-scale projects that require high amounts of water. 

As mentioned before, the bio balls can be used as a supplement to keep your ecosystem in balance. You will still need to install an exterior filter. But it is a great tool to create an environment for your fish where they can thrive and be happy. 

They are not very expensive and easy to use, so why not give them a try? Let us know your experience, and feel free to comment or ask questions below! We are happy to help.  

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