The Fluval FX series is one of the best when it comes to providing the user with the best filters for the aquariums. Coming from a top brand, there are so many things that are going to be right with the model.
The FX4 model is out here to prove that you can always end up with the best canister filter if you know how to research.
The design makes it further easy to set up and maintain if the need arises. You will never have to worry about using this type of model, as it is easy to do so in the first place.
Below are some of the other top features of the model.
Table of Contents
Fluval FX4 Review
High Performance
One thing that you should appreciate about this unit is that the model gives you high performance. The promising results are what will send more people into buying this type of model. You will end up being amazed by the clarity of the final filtered water.
The capacity of the FX4 model at 250 gallons should be able to keep your tanks clean of the murky water. Any contamination should easily be removed when using this model.
The design of the model allows for having filtration media included in it. With more filtration media, then you should have an easier time filtering the water and keeping it clean.
Since the model comes as 5-stage filter, you should not find more contaminants in the filtered water. This is important to keep your aquarium inhabitants in a healthy environment.
As for the flow rate, the pump can deliver up to 700 gallons per hour. Such a high rate of flow rate is going to make most people comfortable with getting such a filter for their tanks.

Setting Up the Model
No need about worrying when it comes to the filter setup part. You can be sure it will be easy to accomplish it in no time.
First, you start with unpacking the media, wash them before placing them in the media basket. Make sure the media is arranged in the filter as recommended by the manufacturer.
The other connections can easily be done by following the detailed manufacturer instructions in the manual. Just make sure that the connections are tight to avoid having issues such as water leaks in the house when the filter is working.
When it comes to priming, the model is designed to be simple and less of pain. The presence of a smart pump technology helps with the priming process. You simply have to add water to the filter and start it. That is all you need to set up and run the filter.
The Smart Pump
This is going to be a point of interest for anyone looking to buy a great filter. The smart pump technology is designed to monitor and optimize the pump performance all the time.
The model achieves this by maintaining the speed of the impeller and pump power to ensure that there is an optimal flow rate at any given time. The pump still checks for any cases of trapped air that might affect the filtration performance. This is done every 12 hours.
As a safety feature, the pump would turn off the motor whenever the impeller is impeded. This further helps protect the filter from any further damage.
The Maintenance
No one likes a model that would demand a lot of maintenance and replacement of parts. As much as the FX4 comes with many handy functions, it is still designed to make the maintenance to be hassle-free. You should have an easy time maintaining as you did with the setup process.
It is possible that sometimes you can forget the maintenance schedule. The model has a monthly indicator dial that will help you never miss any pending maintenance. It is the same for water change to ensure the water quality remains at its best.
The presence of a purge valve is important to prevent issues of water leaks and more mess when carrying out the maintenance of the model.
Low Noise of Operation
When it comes to an external filter, most people do not like one with loud noise of operation. Sitting in a room with such a filter would be unbearable. Things are better with the FX4 model.
It is made to be a high-quality filter with low noise operation. The use of precise engineering helps to create quiet motors makings sure that the room remains quiet even with the filter working.
Pros
- Great design
- Clog-free strainer
- More filtration media
- Easy to perform maintenance
Cons
- It is a bit pricey for some people
Conclusion
If you were thinking about spending money on the best filter, then you have an idea where to start. This model will always assure you of getting the best performance thanks to the best construction.
No more worries about maintenance as the model can easily be cleaned in a few steps. Go ahead and get one for yourself to experience more.
Is there a flow rate vs head height chart available for the FX4? If so, where can I find it?
I’m at about 3.5 or 4ft and I get just a touch over 500 gph output. I did the measurement myself with a 5 gallon bucket and some math. Hoses were cut in half so no custom fitting was done. This is packed with media and filter floss.
Hello I have a 340 litre tank and was looking at buying this but as it’s for up to 1000 litres I’m worried my fish will get blown all over the place especially my Siamese fighter who likes calm water. I’ve already got a 405 and don’t want the 406 as it’s basicaly the same and isn’t great so was looking at the fx4. What do you think?
Siamese is better not put to that risk. Go for some lesser flow filter. If u must still go for the fx4, then think in terms of multiple spray bars. In which case shield the Intake too with a resin rock or similar.
Brilliant filter. I have fx4 and 6. If the power is a bit too much, you can always tune it down with the rotating valves.
I woul,d use a spray bar that can be found on amazon or ebay or make one your self it can be turned down some too
Take some low density foam like 15-30ppi and cut the foam to fit around the fx four output. Take of the flow directional valves they just pop off. Then zip tie the foam around the output. It will not slow your output and you will get nice slow water as it diffuses through the sponge. It will have a current but almost none.
I own this filter and it has stopped purging itself every 12 hours. It is only a couple of months old. Any suggestion on what I can do or what could be wrong with the filter?
Thank you.
If the filter has no air in it the purging will make zero sound and may not shut off. Turn the filter off and turn it back on. Get close to the pump and listed if you hear it slow down or stop it is still working.
Texte me i can recommend
+17077013643
The FX series does a 12hr cycle and auto shutoff and re-start every 12hrs nothing wrong with filter