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What filter media should you use for Fluval G3 and G6?

Are you using a Fluval G3 or G6 Advanced Filtration System but don’t know what filter media to use with it?

This guide at Aquarium Blueprints will help you find the best filter media types based on the specific needs of your fish tank.

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Included with Fluval G3 and G6 Advanced Filters

Both the Fluval G3 and G6 Advanced Filters come with all you needed to get started as you get biological filtration with the Fluval G-Nodes, chemical filtration with the Carbon Media Cartridge and mechanical filtration with the Pre-Filter Cartridge.

Best G3/G6 media for mechanical filtration

Fluval G3/G6 Fine Pre-Filter Cartridge

If you want to filter as much particles out of the water as possible, then we recommend getting the Fine Pre-Filter Cartridge. The super fine pores are designed to trap debris that are as small as 75μ micron in size. The wastes will remain trap until you clean it off.

The Fine Pre-Filter Cartridge should be effective for a very long time as long as you thoroughly rinse off the debris occasionally. If you are interested, you can purchase it for either the G3 or G6 canisters with the following links on Amazon:

Best G3/G6 medias for biological filtration

Fluval G-Nodes Biological Filtration Media

New Fluval G3 and Fluval G6 filters already come with the best biological media available as you will get plenty of Fluval G-Nodes to fill up the media baskets. These media have many fine pores which will give plenty of surface area for nitrifying bacteria to grow on. These colonies will convert the extremely toxic ammonia and nitrite compounds, which come from fish wastes and other decomposing matter, into the much safer nitrate.

We recommend rinsing the G-Nodes frequently as the pores can get clogged up by debris. This can lead to oxygen depletion for the beneficial bacteria living in the pores. You shouldn’t have to replace any of the G-Nodes unless the media starts to break down into little pieces.

If you need some replacements, you can purchase a bag with the following link:

Best G3/G6 media for nitrate filtration

Fluval G3/G6 Nitrate Cartridge

As we stated above, the nitrifying bacteria will convert ammonia to nitrites and then nitrites to nitrates. To get rid of nitrates, you normally have to do a water change. With the said, you can also try the Nitrate Cartridge to keep the nitrates in check.

The G3 version of the cartridge will remove up to 13,000 mg of nitrate ion while the G6 version can remove up to 24,000 mg of nitrate ion in freshwater tanks.

You can replace the cartridge if your water test kit shows any sudden rise in nitrate concentration.

You can purchase the G Series Nitrate Cartridges with the following links:

Best G3/G6 media for phosphate filtration

Fluval G3/G6 Phosphate Cartridge

High phosphate concentration usually leads to excess algae appearing in your fish tank. Although algae is harmless to your fish, you might find them unsightly. If you don’t like the look of algae blooms, then you can use the Phosphate Cartridge.

The G3 version can remove up to 2,200 mg of phosphate ions while the G6 version is capable of filtering up to 3,900 mg of phosphate ions from both freshwater and saltwater tanks.

You can replace the cartridge if you start noticing that algae are rapidly growing in your fish tank.

You can purchase the cartridges with the following links:

Best G3/G6 media for ammonia filtration

Fluval Ammonia Remover (Premium Natural Clinoptilolite)

If you have excess ammonia, then you can use Fluval’s brand of Ammonia Remover, which composes of natural clinoptilolite. The media uses ion exchange to get rid of ammonia from your tank water.

The Fluval Ammonia Remover can be added to the chemical cartridge that comes with the G Series filter. You can replace the clinoptilolite if your water test kit show a spike in ammonia concentration.

You can purchase the remover with the following link:

Best G3/G6 media for heavy metals, odors, discolorations and medicine filtration

Fluval Carbon (Premium Bituminous Carbon)

The included carbon media is great at filtering out heavy metals, odors, discolorations and medicine from your aquarium water. The microscopic pores will trap all of the aforementioned particles and keep them in place.

You can replace carbon if you notice the increase presence any of the aforementioned heavy metals, odors, discolorations and/or medicine in your waters.

If you need more carbon, you can pick up Fluval’s brand with the following link (if the bags don’t fit into the cartridge, you can remove the carbon from the bag and then place them in the cartridge):

Best G3/G6 media for lowering pH

Fluval Aquatic Peat (Compressed Granules)

To make your water more acidic, you need to lower the pH. To do so in a safe manner that won’t stress out and potentially harm your fish, you should add Fluval’s Aquatic Peat Granules to the chemical filtration cartridge of your G3 or G6.

You can replace the compressed granules if your test kit shows that your pH is rising.

You can purchase this filter media with the following link:

Best multipurpose G3/G6 medias for chemical filtration

Fluval G3/G6 Tri-EX Cartridge

The Tri-EX Cartridge is a great multipurpose cartridge that will filter out phosphates and nitrates (freshwater only) in addition to having all the benefits of carbon (which will remove heavy metals, odors, discolorations and medicine).

The cartridge can be replaced if you noticed spikes in any of the aforementioned compounds in your fish tank.

You can purchase the multifunctional cartridge with the following links:

Fluval Sea Total Clear

You can also use Fluval’s Sea Total Clear, which will remove ammonia, nitrate (freshwater only), phosphate, heavy metals, odors, discolorations and medicine from your aquarium.

You can place this media in the carbon cartridge that comes with your canister filter. You can replace as needed if you notice any spikes in the aforementioned unwanted compounds.

You can purchase the filtering product with the following link:

Fluval Zeo-Carb (Super Activated Zeolite and Carbon Mix)

You can also use Fluval Zeo-Carb, which is a mix of carbon and zeolite. The mixture will get rid of ammonia, heavy metals, odors, discolorations and medicine from your fish tank.

You can place the Zeo-Carb in the carbon cartridge. You should replace if you noticed spikes in ammonia or any of the compounds that are removable by carbon.

You can buy the mix with the following link (you may have to remove the Zeo-Carb from the bag first before placing the mixture directly into the cartridge):

Fluval ClearMax (Premium Grade Resin)

One last chemical filtration worth checking out is Fluval ClearMax. The resin will remove phosphate, nitrite and nitrate (freshwater only) from your aquarium.

You can put the ClearMax in the carbon cartridge that comes with your G Series filter. You can replace as needed if your test kit shows spikes in remove phosphate, nitrites and/or nitrates.

You can buy the resin with the following link (you may have to remove the media from the bag before placing them into the cartridge):

Recap

Below is a quick summary on the best Fluval G series media types for specific situations:

  • Mechanical Filtration: Fluval G3/G6 Fine Pre-Filter Cartridge
  • Biological Filtration: Fluval G-Nodes Biological Filtration Media
  • Nitrate Filtration: Fluval G3/G6 Nitrate Cartridge
  • Phosphate Filtration: Fluval G3/G6 Phosphate Cartridge
  • Ammonia Filtration: Fluval Ammonia Remover
  • Heavy Metals/Odors/Discolorations/Medicine Filtration: Fluval Carbon
  • Lowering pH: Fluval Aquatic Peat
  • Phosphate/Nitrate(Freshwater)/Heavy Metals/Odors/Discolorations/Medicine Filtration: Fluval G3/G6 Tri-EX Cartridge
  • Ammonia/Nitrate(Freshwater)/Heavy Metals/Odors/Discolorations/Medicine Filtration: Fluval Sea Total Clear
  • Ammonia/Heavy Metals/Odors/Discolorations/Medicine Filtration: Fluval Zeo-Carb
  • Nitrite/Nitrate(Freshwater)/Algae/Phosphate Filtration: Fluval ClearMax

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