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Fluval

Fluval FX4 High Performance Aquarium Filter, Canister Filter for Aquariums up to 250 Gal.

  • Based on 5,918 reviews
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Availability: In Stock.
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Arrives Sunday, Feb 15
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Size: FX4


Features

  • Multi-stage filter pumps out 700 US Gal (2,650 L) of water per hour, Smart Pump advanced microchip technology continuously monitors and optimizes pump performance
  • Self-starting just add water, plug in and Smart Pump will take over, trapped air auto-evacuated every 12 hours to ensure maximum efficiency
  • Removable, stackable media baskets eliminate water bypass and hold a total of 1 US Gal (3.9 L) of media, all filter media included - mechanical, chemical and biological
  • Compact 16.5 in (42 cm) tall design - easily fits under most aquariums

Description

Fluval FX4 is a high performance canister filter with many outstanding features designed to make aquarium fish keeping easier and more convenient than ever. This super capacity yet compact canister filter has a pump output of 700 gallons of water and has a filter circulation of 450 GPH, which both work to produce cleaner and healthier results. Filtering material can easily be placed in a removable stack of media baskets, which is at the heart of Fluval's multistage filtration. The baskets are precision-engineered to eliminate water by-pass, making filtration more efficient. The baskets can hold a total of 1 gallon of media and can be stacked in the precise combination of layers that will work best for your aquarium. Each one is lined with a foam insert for effective mechanical pre-filtering. Instant-release T-handles let you lift and separate the baskets quickly and easily, making routine maintenance simpler. FX4 also features Smart Pump Technology, which provides optimal filter performance. This advanced technological feature employs an electronic circuit board that continually monitors the pump. Impeller speed and force are constantly measured to ensure powerful output and energy efficiency. It also manages the filter's self-starting feature and evacuates air that may enter or build up within the filtration system. On a 12-hour cycle, the pump will pause and allow trapped air to escape, ensuring the best filtration efficiency. Only 16.5 inches in height, FX4 fits under most aquariums. Fluval first broke onto the aquatic scene in 1975 by introducing the world’s first 3-stage filter with synchronous motor technology. Since then, Fluval has built a legacy around this pioneering spirit, relentlessly adapting in a changing world to launch innovative aquarium products. Fluval’s mission is not just about building products that mimic the natural world, but inspiring aquarists of all skill levels to enjoy and respect the hobby for generations to come.

Brand: Fluval


Color: Black


Material: Plastic, Stainless Steel


Style: Canister


Product Dimensions: 15.6"L x 15.6"W x 15.6"H


Power Source: Corded Electric


Item Weight: 6.43 Kilograms


Maximum Flow Rate: 2650 Liters Per Hour


Global Trade Identification Number: 48


Manufacturer: Rolf C. Hagen (USA) Corp.


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 15.6 x 15.6 x 17.7 inches; 14.17 Pounds


Manufacturer recommended age ‏ : ‎ 1 month and up


Item model number ‏ : ‎ A214


Date First Available ‏ : ‎ July 17, 2016


Manufacturer ‏ : ‎ Rolf C. Hagen (USA) Corp.


Best Sellers Rank: #8,135 in Pet Supplies (See Top 100 in Pet Supplies) #24 in Aquarium Filters


#24 in Aquarium Filters:


Customer Reviews: 4.4 4.4 out of 5 stars (6,023)


Brand: Fluval


Color: Black


Material: Plastic, Stainless Steel


Style: Canister


Product Dimensions: 15.6"L x 15.6"W x 15.6"H


Power Source: Corded Electric


Item Weight: 6.43 Kilograms


Maximum Flow Rate: 2650 Liters Per Hour


Global Trade Identification Number: 48


Manufacturer: Rolf C. Hagen (USA) Corp.


UPC: 015561102148


Specific Uses For Product: Indoor


Item Weight: 14.14 pounds


Item model number: A214


Date First Available: July 17, 2016


Item Package Dimensions L x W x H: 17.6 x 15.67 x 15.31 inches


Item Dimensions LxWxH: 15.6 x 15.6 x 17.7 inches


Brand Name: Fluval


Target Audience Keyword: fish


Directions: Please see packaging for directions.


Country of Origin: Italy


Warranty Description: 3 Year Limited Warranty The Fluval FX4/FX6 High Performance Canister Filter is guaranteed against defects in material and workmanship under normal aquarium usage and service for 3 years from date of purchase. Non-replaceable and non-serviceable parts will be repaired or replaced at Rolf C. Hagen Inc.’s discretion, free of charge, when the complete filter is returned with all components along with a valid proof of purchase and postage paid. This warranty does not apply to any filter that has been subject to misuse, negligence or tampering. It does not apply to filters which have been incorrectly assembled or unsuitably maintained or where installation and maintenance instructions have not been followed correctly. The warranty does not apply to wear and tear parts such as the impeller, impeller cover or motor seal. No liability is assumed with respect to loss or damage to livestock or personal property irrespective of the cause thereof. Before returning the filter under warranty terms, please ensure that all setup and maintenance instructions have been followed. If you are in doubt, please contact your local aquatic specialist retailer for further advice before returning the product. THIS DOES NOT AFFECT YOUR STATUTORY RIGHTS.


Model Name: Fluval FX4 High Performance Canister Filter


Size: FX4


Age Range Description: All Life Stages


Number of Items: 1


Included Components: Product in Descripton


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Feb 15

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • Run, don't Walk. Get you one NOW
Size: FX2
Review Image by Tammie Durham Tammie Durham
Absolutely! Hands down the best canister filter out there. If you don't have one and you're waiting, stop, go get it now, you won't regret it. There is no noise. It's easy to install. The flow rate is superb. Water clarity is spectacular. You couldn't ask for anything better. Go get you one! What are you waiting for? ... show more
Reviewed in the United States on December 12, 2025 by Tammie Durham Tammie Durham
    • Simply the best filter on the market.
Size: FX6
The Fluval FX line of filters is a real work horse which rarely goes wrong if you do the upkeep on it. I use one on the tank I have my turtle in, and it keeps the water crystal clear, even though the old boy digs a lot an tries everything he can to cloud up the water. If I take it off line for cleaning (which is a breeze) or maintenance, it will get the water clear again within an hour if the turtle has been very active while it was off, and much sooner if he wasn't moving around too much. He's a very active turtle, and a very messy eater, but he's neither active enough nor messy enough to overwhelm the FX-6. I also use an FX-6 on my hillstream tank which requires a lot of flow. It pushes the water through at a very good clip so that the stream has a pretty good current for my hillstream loaches and for my rainbow shiners to run in when they're getting ready to spawn. I have the FX-4 on a 20 gallon tank which is probably just a bit overpopulated, But again, it is a good enough filter that it keeps the water quite clean. With surface skimmers on my tanks, even the water's surface is clear. To clean the filter media, all you need to do is lift the media baskets out, the use the filter's bucket to clean the sponges and reusable media, replace the media which has broken down too much to be reused, or which uses chemical treating, then either empty the old water out and replace it with fresh clean, or keep the old water if it's not too bad (it is almost always too bad). The reason you clean the media in the water the filter bucket has in it is so that you don't loose any of the beneficial bacteria which is growing in it. The FX series of filters have variable flow valves, which is a nice feature, though many filters have that. If you close the valves before opening the lid of the filter, you don't have to worry about draining the hoses, and they will be good to go when you turn the filter back on and open the valves. No priming needed. Everything in this filter is easily repairable if something goes wrong. If something happens which wears out the impeller, it's very easy to take the old impeller out, and drop a new one in. It's also easy to replace all the O-rings when they get old and start to loose their ability to seal the unit. If you're unlucky, you might need to do that once a year, but it's more likely that you'll just need put new lubricant on them. I am mechanically challenged, so if I find it easy to take care of, I'm sure just about anyone will be able to do it. I have had problems with several of the other big brands of filter makers, but I have never had a Fluval FX series filter go south on me. I recommend them to anyone who wants to keep their fish's environment clean and healthy. If I ever start another tank, I'll definitely be buying another Fluval FX. ... show more
Reviewed in the United States on October 24, 2024 by K. Porterfield
    • Send it!!! You won’t regret it.
Size: FX6
Ive been running the Fluval for about 3 months now, and I am absolutely OBSESSED with its quality. I have a 75 gallon tank with a turtle and pleco (both produce A LOT of waste). Previously I was a die hard Penn Plax Cascade fan for the last 5 years, but my last two had motor failures and they changed their warranty terms finally, so I decided to switch it up. Long ago I wanted a Fluval, but but the price was steep so I settled for less and let me just say it’s the best investment you can make. It’s quiet (don’t know why other reviews say it’s not unless they are keeping their water levels really low), my tank remains crystal clear with my normal monthly maintenance routine, and it is easy to clean and change out my media. The fasteners are really not that complicated and don’t take that long to unlock like other reviews say. The canister itself is designed so that it is air tight and I’ve had no signs of leaking. The outtake is made so you have two options to direct the flow of your water which is helpful if you have a basking platform above half of your tank. Highly recommend. ... show more
Reviewed in the United States on October 1, 2025 by Carley
    • I wish I had gotten this for my tank sooner!
Size: FX2
I have two turtles and their tank was always so dirty! I have gone through 6 HOB filters and two aesthetic turtle filters (ones that look like rocks) and every filter I tried needed to be fully taken apart and deep cleaned every few weeks! Nothing could keep my tank clean until I got this filter! I waited a few months to write this review just to make sure it held up and it is still absolutely amazing! I was nervous because I have never had a canister filter before and I didn’t know how to use it but it’s actually incredibly easy. It’s effective, super quiet, and total game changer for my turtles! Now I’m thinking of switching all of my tanks to this filter! It saves me so much time and it saves money because I don’t need to constantly buy replacements for the HOB filters anymore! ... show more
Reviewed in the United States on November 15, 2025 by Jackie Carmel

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