When you purchase through affiliate text and image links on Aquarium Blueprints, we may earn a commission.

Best filter medias for Fluval FX4, FX5 and FX6

Do you have a Fluval FX4, FX5 or FX6 canister filter but don’t know what filter media to use? This guide will help you find the best filter media types based on the specific needs of your fish tank.

Quick Navigation:

Fluval FX4/FX5/FX6 Media Baskets

The Fluval FX4, FX5 and FX6 High Performance Canister Filters have the same sized grey-colored media basket and red-colored filter half media basket. You can take a look at what each looks like below:

Grey Media Basket:

Red Half Media Basket:

Included with FX4/FX5/FX6 Canister Filters

Fluval bundled some filter medias with new FX4, FX5 and FX6 Canister Filters. You can check out what’s included in each model below:

FX4:

  • 4x FX Filter Series Foam Pads
  • 1x FX Filter Series Bio-Foam+
  • 2x Biomaxes
  • 1x FX Filter Series Carbon Foam

FX5:

  • 6x FX Filter Series Foam Pads
  • 0x FX Filter Series Bio-Foam+
  • 0x Biomax
  • 0x FX Filter Series Carbon Foam

FX6:

  • 6x FX Filter Series Foam Pads
  • 2x FX Filter Series Bio-Foams+
  • 2x Biomaxes
  • 1x FX Filter Series Carbon Foam

Best FX media type for mechanical filtration

Fluval Max-Clean (Superior Mechanical Filtration)

If you want to remove as many small debris as possible from the water in your aquarium, then you should get the Fluval Max-Clean. The fine polyester pads are designed to capture the smallest of visible wastes in the canister filter.

You can place the Fluval Max-Clean on the red half media basket. You should replace this filter media if you noticed that your water flow has been notably reduced as a result of being clogged by the dirty pad.

You can purchase the Fluval Max-Clean on Amazon.

Fluval Pre-Filter (Premium Mechanical Filtration)

For additional mechanical filtration, you should also get the Fluval Pre-Filter. The rings will help trap medium-sized and big particles from the water column.

You can put the this filter media on the grey media basket. You shouldn’t have to replace the rings unless they start breaking down into pieces. An occasional rinse to get rid of the debris should be good enough to maintain their effectiveness.

You can buy the Fluval Pre-Filter with this link.

FX Filter Series Foam Pad (Biological and Mechanical Filtration)

The included FX Filter Series Foam Pads is also excellent at filtering out fish wastes and other particles from your fish tank. Since these are long lasting, the foam also provide plenty of surface area for nitrifying beneficial bacteria to grow (which will remove the harmful ammonia and nitrites from your aquarium).

You can put the foam pads on the outer rim of the grey filter basket. You only need to replace the foam once it starts to break down. Otherwise, they will remain useful with regular rinsing.

If you need replacements, you can buy a pack here.

Best FX media types for biological filtration

Biomax (Maximum Biological Filtration)

The Biomax, which is already included with new FX4 and FX6 canisters, is the best at providing biological filtration. The micro pores give a lot of surface area for the aforementioned beneficial bacteria colonies to grow on.

The Biomax can be placed in the grey media basket. You shouldn’t have to replace these media types unless they break down into finer pieces. You should make sure that you rinse them regularly, however, as the clogged pores could kill off your beneficial bacteria due to the lack of oxygen.

If you need more Biomax, you can purchase a pack on Amazon.

FX4/FX5/FX6 Bio-Foam+ (Superior Biological Filtration)

You can also pair the Biomax rings with the Bio-Foam+. The sponge contains a lot of fine pores, making it a great material to grow nitrifying bacteria. Of course, the foam will also capture any debris from the water in your fish tank.

You can put the Bio-Foam+ in the red half media basket. To keep the beneficial bacteria colonies healthy, make sure you rinse off the foam occasionally to prevent potential oxygen depletion due to clogged pores. You can replace the media if it starts breaking down.

If you need more Bio-Foam+, you can purchase a bundle with this link.

Best FX media type for ammonia filtration

Fluval Ammonia Remover (Premium Natural Clinoptilolite)

If you want to remove ammonia from your aquarium, then you should get the Fluval Ammonia Remover. The included clinoptilolite uses ion-exchange to remove the toxic compound from the fish tank.

The Fluval Ammonia Remover can be put in the grey media basket. You should swap out the clinoptilolites and replace them with new ones if you noticed that you are getting spikes in ammonia after testing your aquarium water.

Buy the Fluval Ammonia Remover here.

Best FX media type for heavy metals, odors, discolorations and medicine filtration

Fluval Carbon (Premium Bituminous Carbon)

To filter out heavy metals, odors, discolorations and/or medicine, you should use Fluval’s brand of carbon. The microscopic pores are designed to trapped any of the aforementioned unwanted compounds from the tank water.

The bituminous carbon can be placed in the grey media basket. You can replace this media on a monthly basis or sooner if you noticed that the carbon is losing its effectiveness.

You can purchase the Fluval Carbon on Amazon.

Best FX media type for lowering pH

Fluval Aquatic Peat (Compressed Granules)

If you want to make your tank water more acidic, then you should use Fluval’s brand of peat moss. This material will slowly and, more importantly, safely lower the pH.

You can put the compressed granules in the grey media basket. You can replace the moss if your test kit shows that the water in your fish tank is showing an increase in pH.

Buy the Fluval Aquatic Peat with this link.

Best media types for multipurpose chemical filtration

Fluval Sea Total Clear

The best multifunctional chemical filtration available for the Fluval FX4, FX5 and FX6 Canister Filters is the Fluval Sea Total Clear. Since it uses a combination of carbon and resin, the special blend will be able to remove ammonia, nitrate (freshwater only), phosphate, heavy metals, odors, discolorations and medicine.

You can place the Fluval Sea Total Clear on the grey media basket. You can replace the mixture if your test kit shows spikes of ammonia and/or nitrates. You can also swap them out if you notice any increase in heavy metals, odors, discolorations and/or medicine.

Purchase the Fluval Sea Total Clear here.

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

The Fluval Zeo-Carb uses a mix of zeolite (which will remove ammonia) as well as carbon (which will get rid of heavy metals, odors, discolorations and medicine).

You can also put the Fluval Zeo-Carb on the grey media basket. You can remove the old mix and add in a new mix if your test kit shows an ammonia spike. You can also replace the substance if you notice a rise of heavy metals, odors, discolorations and/or medicine.

You can buy the Fluval Zeo-Carb on Amazon.

Fluval ClearMax (Premium Grade Resin)

If you want to remove phosphate, nitrite and nitrate (freshwater only), then you should check out the Fluval ClearMax.

The premium grade resin can be placed into the grey media basket as well. Remove and replace the substance if you notice spikes in nitrites, nitrates and/or algae in your tank water.

The Fluval ClearMax is available for purchase with this link.

Recap

You can find a quick summary for the best Fluval FX media types, based on for specific situations, below.

  • Mechanical Filtration: Fluval Max-Clean, Fluval Pre-Filter and FX Filter Series Foam Pad
  • Biological Filtration: Biomax and FX4/FX5/FX6 Bio-Foam+
  • Ammonia Filtration: Fluval Ammonia Remover
  • Heavy Metals/Odors/Discolorations/Medicine Filtration: Fluval Carbon
  • Lowering pH: Fluval Aquatic Peat
  • 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

Resources: