Fluval Canister Filter, FX6 Filter (400 Gal) Review

Review of Fluval FX6 Canister Filter: External Canister Filter

Ease of Use:
5 Stars
5 Stars
5 star
Value for money:
4 star
Self-priming system makes it easy to use.The filter has excellent features for optimal performance.Has smart systems and maintenance reminders to make your work easier.Offers great value for money considering its features and performance.
  • Aqua valves makes maintenance easy
  • It has a maintenance reminder
  • The filter has a high capacity
  • It features a clog-free strainer
  • The filter works quietly
  • Has an automatic priming system
  • It comes at a high price
  • The heavy weight makes it hard to move
  • Small fish could get sucked in to the filter

The Fluval FX6 Canister Filter is a great filtration system for large aquariums. It is far more reliable and powerful than the other aquarium filters of the same class. This multi-stage filter can pump up to 925 gallons per hour. It comes with media baskets and a media filter, both of which are reliable, and assure you of good performance.

Changing the water is very easy thanks to the drainage valves, so you don’t have to deal with lifting heavy buckets. The filter is about 21-inch tall, so it would fit perfectly in most large aquariums. The Fluval FX6 also has an anti-clog telescopic strainer that ensures a continuous water flow. Impressed yet? Read on to find out what this filter can really do for your aquarium. With all these and much more, keep reading to find out the usefulness of this canister filter.


As an aquarium owner, you already know the importance of having the right filter in your fish tank. The Fluval FX6 canister filter is an outstanding filter that has been designed for aquariums up to 400 gallons. It is an excellent filter that provides many advantages and durable performance.

The filter is an upgrade of the FX5 that was designed for aquariums up to 300 gallons with a more enhanced filtration system. As compared to the previous model and other canister filters, there are a lot of things that you will like about this filter. Not only did the manufacturer upgrade the filtration capacity but also added several other great features to enhance its performance.

Who is this product for?

Though this filter is suitable for large tanks with up to a 400-gallon capacity, it is also great for users who want superior filtration performance in smaller aquariums. And this work just as good for saltwater tanks as for freshwater  aquarium.

The filter features a user-friendly design making it easy to use for both experts and beginners. The self-priming system makes starting up the filter pretty fast. Also, it has a reminder that alerts you when you need to do maintenance for efficient use. You will also get a user manual with detailed explanations on all the steps that you need to follow when maintaining the filter.

However, considering the high price of this canister filter, it might not be a suitable option for aquarium owners looking for a more affordable option.

What’s included in the Package?

If you are planning to buy this canister filter, you should know what is in the box. The filter comes with all the necessary items that you would need. You won’t have to buy any additional item. The box includes the following:

  • 3 media baskets 
  • Output nozzle and intake stem
  • Aquastop valves
  • Utility valve hosting
  • Strainer
  • Canister
  • Filter lid
  • Ribbed housing
  • Rim connectors
  • Pump unit and power cord
  • Rubber feet

On top of that, you will also get four media filters:

  • Biomax for biological filtration
  • Foam for mechanical filtration
  • Biofoam for biological filtration
  • Carbon pads for chemical filtration

Check this link for unboxing video:

Overview of Features

The Fluval FX6 has some excellent features that make it stand out from other models on the market today. It has a three-stage filtration filter with mechanical, chemical, and biological filtration. Its large capacity makes it suitable for large aquariums with up to 400 gallons. Other essential aspects that you will love include the following.

Quiet Operation

Not only does this canister filter provide a high capacity, but it also provides a silent operation. In fact, you might not notice it at all unless you come very close to the filter. It features quiet motors that offer a smooth and silent operation without vibrations. As compared to other canister filters, you will note that this model has the lowest noise level.

Self-priming start system

This is a great feature that makes the installation much easier. Usually, it can be tough to siphon water in the canister before the filtration process begins. The self-priming feature fills the water automatically in the filter before starting the filtration process. This takes only about 2 minutes to fill the water.

Aqua Stop Valves

Just like any other aquarium filter, maintenance from time to time is crucial for efficient filter performance. It is extremely easy to maintain this filter because it has a stop-valves to simplify process. You simply need to turn the valve lever to stop the water flow. You can then separate the hose valve and do the maintenance without worrying about damaging the filter components or leakages.  After the work is complete, turn the valve lever back to its original position and the water will start flowing again.

Continuous System Monitoring

The filter has an electronic circuit board that monitors the performance of the filter. Continuous monitoring ensures that there is an optimal output when the filter is working. In case a problem occurs, it is easier to sort it out if you know of it right away.

Multi-Directional Output

This filter features a multi-directional output so you can be sure of effective distribution of water in all parts of the aquarium. This filter also has a dual filter that you can adjust to suit your requirements to achieve an equal water flow.

Clog proof Intake

This is another important feature that improves water flow. The filter’s intake tube has a strainer to prevent debris from entering the filter. You dont have to suffer any clogs with this unit. However, you need to be cautious with small fishes since they can get sucked into the intake.

Installation and Ease of Use

If you are installing a canister filter for the first time, you might find it a little tricky. However, the process is actually not that hard thanks to the self-priming system. You will also get detailed instructions from the manual to help you install the filter. The instructions are straightforward and easy to follow.

You can also watch this video to get further details on the installation.

Fluval FX6 Filter Alternatives

Another alternative to the Fluval FX6 filter is the SunSun Sun HW-704B 525 GPH 5-Stage External Canister Filter. This canister filter provides a 5 stage filtration, and it is equipped with a 9W UV sterilizer. The sterilizer works amazingly well in controlling algae spores and bacteria to ensure that your fish get clean water. This filter also comes at an affordable price as compared to the FX6 model.


We hope, that this Fluval FX6 canister filter review has provided a means of you placing your trust in this product as a worthwhile investment. It has a lot of excellent features, painless to use and one of the easiest filters when it comes to cleaning and maintaining. In as much as it is an expensive filter, it beats many canister filters on the market today. Get this model if you have a large tank and need a filter that works silently. 

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