Aquarium maintenance can often be a challenging task, particularly when it comes to ensuring its cleanliness and safety. However, using bio balls and biological filter media can greatly assist aquarium owners in their efforts to maintain the well-being of their fish. In addition to regularly removing waste and debris from the tank, it is crucial to regularly monitor and regulate the levels of ammonia, nitrites, and nitrates in the water. These chemical compounds can be difficult to manage and often require rigorous upkeep and testing.
Thankfully, bio balls and biological filter media can help regulate these potentially dangerous byproducts. These products house nitrifying bacteria that scrubs your water clean by consuming ammonia and nitrites.
Below, we’re going to dive into the best bio balls and biological filter media available and discuss everything you need to look for when purchasing them for your aquarium. Let’s get started!
Table of Contents
Recommend Bio Balls for your Aquarium:
Top 6 Picks for Best Bio Balls and Biological Filter Media
First, we’re going to review our top 6 picks for bio balls and biological filter media. We’ve gone through some extensive side-by-side testing of countless options available so you don’t have to. These are our all-around favorites.
What we Like
- Large surface area
- Safe for freshwater and saltwater
- Won’t clog
- Come in large quantities
Aquatic Experts Bio Balls Filter Media – 1.5 Inch
These bio balls have a unique shape with columns that contain a massive amount of surface area to house impressive bacteria colonies. They are 1.5” in diameter and are likely too large for smaller aquariums.
They are made entirely of polypropylene, so they’re safe for freshwater and saltwater aquariums or ponds. They also don’t clog and require little maintenance.
They come in large quantities, but they are relatively expensive.
The column shape allows for some compression, so you can pack these bio balls into just about any tight space in your tank.
Features
- Durable
- Flexible for easy packing
What we like
- Large surface area
- Safe for freshwater and saltwater
- Won’t clog
- Come in large quantities
What we don’t like
- Too large for small tanks
- Expensive
What we like
- Excellent surface area
- Won’t clog
- Very affordable
- Suitable for saltwater and freshwater
Marineland Bio-Filter Balls
These bio balls have a good surface area for large bacteria colonies to live. They are straightforward to clean and won’t clog easily, but they do provide less surface area than our top pick or other options with filter sponges.
These bio balls are very affordable and come in large quantities. They’re just under an inch in diameter. They’re suitable for smaller aquariums but are likely too small for larger filters.
They’re made of polypropylene and are safe for saltwater and freshwater use.
Features
- Durable
- Won’t snag on each other
What we like
- Excellent surface area
- Won’t clog
- Very affordable
- Suitable for saltwater and freshwater
What we don’t like
- Smaller surface area than our top pick
- Only suitable for small aquariums
What we like
- Enormous surface area
- Can house denitrifying bacteria
- Suitable for freshwater and saltwater
CerMedia MarinePure 1.5-Inch Sphere Bio-Filter Media
These bio balls are ceramic and contain countless pores for an immense surface area. Unlike non-porous bio balls, they can house denitrifying bacteria as well as nitrifying bacteria.
The ceramic promotes better bacteria growth than plastic but will clog far more easily and require more maintenance. The ceramic will also break if dropped during cleaning.
These are suitable for freshwater and saltwater tanks. They’re 1.5” in diameter, so they may be too large for smaller filters. The rigid material doesn’t allow for any compaction.
They are relatively expensive, especially since they aren’t as durable as polypropylene bio balls.
Features
- Won’t get caught on other bio balls
- Extremely porous
What we like
- Enormous surface area
- Can house denitrifying bacteria
- Suitable for freshwater and saltwater
What we don’t like
- Clog more easily than plastic options
- Less durable than plastic
- Not flexible
What we like
- Enormous surface area
- Can house denitrifying bacteria
- Affordable
- Suitable for freshwater and saltwater
Seachem Matrix Bio Media
This biological filter media is made of mined rock that is naturally porous. It provides an impressive surface area for maximum nitrifying and denitrifying bacteria growth. However, the pores can easily get clogged, so this media will need frequent maintenance.
They aren’t uniform in their shape or size, and they don’t flex at all. As such, they may take longer to situate effectively in your filter.
The rock can degrade over time and leave some residue in your aquarium. They need to be washed thoroughly before use to remove the loose particles.
These rocks can break if dropped during cleaning.
Features
- Made of natural material
- Very useful for reducing nitrites
What we like
- Enormous surface area
- Can house denitrifying bacteria
- Affordable
- Suitable for freshwater and saltwater
What we don’t like
- Can clog easily
- Can degrade over time
- Need extensive rinsing before use
- Can break if dropped
What we like
- Enormous surface area for bacteria growth
- Can house denitrifying bacteria
- Won’t raise your tank’s pH
- Suitable for freshwater and saltwater
Fluval Biomax Bio Rings
These bio rings are made of a highly porous ceramic that provides ample surface area for large nitrifying and denitrifying bacteria colonies. The small pores do lead to clogging, so these will require routine cleaning and maintenance.
They need to be rinsed thoroughly before use to remove loose particles, and they can release these particles into your aquarium as they degrade over time.
They are suitable for large and small filters, given their size. They are relatively expensive, and the need for replacement will add to the ongoing cost.
Unlike many ceramic options, these won’t increase your water’s pH.
Features
- Natural material
- Don’t affect your water quality
What we like
- Enormous surface area for bacteria growth
- Can house denitrifying bacteria
- Won’t raise your tank’s pH
- Suitable for freshwater and saltwater
What we don’t like
- Need to be replaced every so often
- Need rinsing before use
- Degrade over time
- Somewhat expensive
What we like
- Provide an immense surface area for bacteria growth
- Can house denitrifying bacteria
- Suitable for freshwater and saltwater
- Great for smaller filters
EHEIM Substrat Pro Biological Filter Media
This filter media is made of porous glass material and provides a vast surface area to promote nitrifying and denitrifying bacteria growth. The small pores do get clogged easily and will need to be cleaned frequently.
This natural material will degrade over time and should be replaced every 6 months or so. They are relatively expensive, and the need for replacement increases ongoing costs.
They need to be rinsed thoroughly before use and can leave particles in your filter as they degrade.
They are mostly round in shape and can pack into small filters despite not being flexible.
Features
- Natural material
- Extremely porous
What we like
- Provide an immense surface area for bacteria growth
- Can house denitrifying bacteria
- Suitable for freshwater and saltwater
- Great for smaller filters
What we don’t like
- Can get clogged easily
- Degrades over time
- Relatively expensive
- Require extensive rinsing before use
Why do I need a biological filter?
Many aquarium owners wonder why a biological filter is needed if they already have mechanical filtration running in their tank. Mechanical filters parse larger material like excrement and uneaten food particles, but biological filters remove smaller contaminants.
Natural byproducts in your tank can cause spikes in ammonia, nitrites, and nitrates. These compounds are harmful to your fish in large quantities and aren’t filtered out by mechanical filtration.
Biological filters provide ample surface area for Nitrosomonas and Nitrobacter, the bacteria that consume these harmful compounds and make your tank a safer place for your fish to live.
The bacteria will begin to grow on your bio balls or biological filter media naturally and scrub your water clean of harmful byproducts.
How to use bio balls in an aquarium
Bio balls are not meant to catch large particles in your tank, so they are most effective when they’re placed immediately after a physical filter or filter floss. They won’t get clogged by food particles or excrement when situated behind a mechanical filter.
They can be submerged entirely but are most effective in moving water. The bacteria also need oxygen to stay healthy, so hanging them in the stream of water pouring into your tank from your filter is the best placement.
Bio balls naturally attract healthy bacteria and will begin harboring colonies shortly after they are introduced to your system.
The different types of bio balls and biological filter media (BFM)
There are several different kinds of biological filters, each with its advantages and disadvantages. Bio balls and BFMs can be made of plastic, porous ceramic, or porous glass materials.
Plastic bio balls offer the least amount of surface area because they aren’t porous. They can’t house denitrifying bacteria because their surface is exposed to oxygen. However, they don’t clog, never degrade, and require very little maintenance. Most are flexible and allow for compaction into a filter.
Ceramic biological filter media are incredibly porous and provide immense surface area for bacteria growth. They can harbor both nitrifying and denitrifying bacteria. However, they degrade over time, aren’t flexible, need extensive rinsing before use, and need to be replaced and cleaned regularly.
Porous glass biological filter media are often the most porous and provide the best surface area. The pores are tiny, though, and can quickly become clogged. They need frequent replacement and cleaning and are harder to situate in your filter, given their rigidity.
Benefits of using bio balls and biological filter media
Bio balls and biological filter media are a requirement in all aquariums and ponds. They have numerous benefits that promote a healthy marine environment:
1. They remove ammonia from your tank water. Ammonia is a natural waste product from fish, but the buildup of ammonia can be detrimental and even toxic to fish. Biological filter media, including bio balls, naturally rid of the compound and can get your ammonia levels down to 0 ppm.
2. They remove nitrites and nitrates from your aquarium. These compounds are common in overcrowded tanks or as a result of overfeeding. They can inhibit oxygen transfer in your fish and lead to suffocation.
3. They naturally promote a healthy ecosystem. The bacteria that cling to the surfaces of bio balls and biological filter media naturally occur in your tank. Your biological filters merely provide generous living space for healthy bacteria and allow for natural filtration of dangerous and potentially toxic materials in your aquarium or pond.
4. They get rid of the need for chemical additives. Many aquarium owners turn to chemicals to treat high levels of ammonia and nitrogen. While chemicals can help balance pH and remove harmful compounds, they can be overused and create dangerous living environments for your fish.
5. They reduce cleaning and maintenance needs. Biological filters help keep your water clean and clear. Maintenance and routine cleaning will always be needed, but biological filters can keep your tank cleaner for more extended periods in between cleanings.
Things to look for in good bio balls and biological filter media
There are many options for bio balls and biological filter media available, but not all are created equal. Make sure you consider the below essential features when choosing a biological filter for your tank.
Surface Area
One of the most important features when considering bio balls or a biological filter media is surface area. Your bio-filter will serve as a home for healthy bacteria, so the more surface area it has, the more bacteria it can support.
Clogging Potential
Porous materials are excellent biological filter options that offer the most surface area. However, smaller pores can get clogged more easily and frequently.
Polypropylene bio balls generally offer the least surface area, but they never clog and require almost no maintenance. Porous ceramic and glass materials provide a generous surface area but can clog easily and require more frequent cleaning.
Material
Next, you’ll want to consider the material that makes up your bio ball or BFM. Non-porous plastic offers a smaller surface area but is flexible and won’t degrade over time. It generally doesn’t need replacement.
Ceramic, natural stone, and glass break down, can leave particles in your aquarium or pond, and need to be replaced as they degrade.
Size
Lastly, consider the size of the bio ball or media you’re purchasing. Larger bio balls or media pieces may not be suitable for smaller filters, while smaller options can clog more easily from food particles or debris in your tank and require more frequent cleaning.
Bio Ball and Biological Media FAQs
In what order should I use biological filter media (BFM)?
Biological filter media should be placed after a mechanical filter to prevent clogging. Bio balls are most effective when placed in the stream trickling into your tank from your filter. BFM and bio balls can also be placed in your filter canister.
Avoid placing BFM that can degrade in the bottom level of your filter. The second tray from the bottom of your canister is best.
What is the difference between bio balls and ceramic rings?
Bio balls and ceramic rings are two of the most common types of biological filter media used in aquariums. Each one functions in a slightly different way.
Bio balls are not porous and instead rely on a smaller surface area for bacterial growth. Ceramic rings have countless tiny pores that all house bacteria.
Bio balls can’t hold nearly as large of a colony as ceramic rings, but they also don’t have pores that can clog. As such, ceramic rings require more frequent maintenance to prevent or fix clogging.
Ceramic rings can also house both nitrifying and denitrifying bacteria due to the absence of oxygen deep inside the pores.
What precautions do you need to take when using bio balls?
Most bio balls are safe for use in all marine environments, but you should choose balls that are suitable for your tank. Check the bio balls to ensure they are safe for saltwater or freshwater tank.
Additionally, you should make sure to place your bio balls after a physical filter to prevent clogging.
How do you clean bio balls?
Cleaning bio balls is very straightforward. You should remove the balls from your filter and place them in a small amount of your tank water – never use tap water for cleaning. Swirl them around to remove food particles or waste, then put them back in your filter canister.
Do bio balls need to be replaced?
Bio balls made of polypropylene never degrade and won’t need to be replaced. With regular cleaning, your bio balls will clean your tank indefinitely.
How long does it take for bacteria to grow on bio balls?
Beneficial bacteria already exist in your settled tank. However, it will begin to form on the surface of the bio balls within 24 hours. After a week or so, there will be viable colonies growing on the surface.
How many bio balls are needed per gallon?
The number of bio balls needed per gallon of water depends on the surface area and size of the balls. Check the manual of the bio balls you purchase, but a quantity is a volume of about a half-gallon of bio balls per 25 gallons of water.
How long does bio media last?
The lifespan of your biological filter media depends on the specific product. Polypropylene bio balls will last indefinitely. Ceramic, stone, and glass BFMs generally last about 6 months to a year before degradation detracts from their filtering capability. Some ceramic options last longer but will usually need to be replaced within 1-2 years.
Conclusion
Bio balls or another biological filter medium should be an integral filtration method in every aquarium. They naturally remove harmful ammonia, nitrites, and nitrates that can be toxic to fish. They reduce maintenance of your tank and can rid of the need for chemicals that can make aquarium imbalances worse and more harmful.
Our top pick for a BFM for your aquarium is Aquatic Experts’ Bio Balls. They’re low maintenance, suitable for all marine environments, and have an excellent surface area to promote abundant growth of beneficial bacteria.