Whether you’re keeping tropical fish, goldfish or a saltwater aquarium, clear, clean water is essential for having healthy fish, plants and invertebrates. Canister filters are regarded as a step up from basic hang-on-back (HOB) aquarium filter. Aquarium canister filter systems are engineered to provide more effective filtration for freshwater and marine aquariums. Bigger is better with aquarium filters!
Canister filters use a greater volume of advanced and specialty filtration media that remove toxins, improve water quality and maintain water clarity. The high flow volume of a canister filter is unmatched compared to other types of aquarium filters. If you’re starting a new aquarium or just want to upgrade your filtration system, we’ve compiled a list of the best aquarium canister filters available today. Maybe you don’t know much about aquarium filtration. Don’t worry! We’ll explain everything you need to know to make the right choice!
- Benefits Of Using A Canister Filter
- The Top Ten Canister Filters In 2021 Review
- 1 Fluval 406 MSF canister filter
- 2 Sunsun 4-Stage Canister Filter with 9-watt UV Sterilizer
- 3 Fluval FX6 canister filter
- 4 Hydor 250 Professional Canister Filter
- 5 Penn Plax Cascade 1500 Canister Filter
- 6 Hydor 600 Professional Canister Filter
- 7 EHEIM Classic External Canister Filter with Media
- 8 AquaTop CF Canister Filter
- 9 Marineland Magniflow Canister Filter
- 10 API Filstar XP Large Canister Filter
- Best Canister Filters for Aquariums Buying Guide
Benefits Of Using A Canister Filter
Are Canister Filters Worth The Upgrade?
You may be wondering what’s so great about canister filters. It’s true all aquarium filters circulate the water and filter the water, but that’s where the similarities end. Hang-on-back filters use a filter cartridge. The filter cartridge consists of a “pocket” made of synthetic fibers. Activated carbon, usually a very small amount, is added to the pocket. Water flows through the cartridge, where particles of debris are captured on the fiber pocket. The small amount of activated carbon will remove a trace of dissolved organics, color and odors, but not much.
A Canister filter is a “no compromise” filter. The large canister holds significantly more filtration media. The bottom line is canister filters are able to capture more debris, circulate more water and remove more organic pollutants that discolor the water, cause odors and stress the fish, than ordinary hang-on-back filters. We’ve checked out a lot of canister filters. Here what we found out.
The Top Ten Canister Filters In 2021 Review
1 Fluval 406 MSF canister filter
Fluval is a brand famous for powerful aquarium filtration. For over 30 years Fluval has been continuously upgrading their canister filter range to make them more powerful and efficient. The MSF logo stands for multi-stage filtration. Large media baskets stack together, providing stages of filtration. Each basket contains different filter media. Water passes through the baskets where the filter media remove particulate matter, dissolved organics, colors and odors. Biological filter media will remove ammonia and nitrite.
A major complaint with less reliable canister filters is leaking seals. The Fluval 406 has been upgraded with reliable seals and quick-release hose connectors. Better seals mean the canister won’t leak.
The Fluval 406 comes with a variety of mechanical, chemical and biological filter materials, each specially designed for the Fluval media baskets. The Fluval 406 canister filter comes with:
- 4 x foam filter pads
- 4 x 70 g activated carbon
- 2 x polishing pads
- 2 x 120 g BioMax ceramic media
- 2 x Bio-Foam biological filter media
- Flow Rate: 1450 LPH (383 US GPH)
- Rated for tanks up to 100 gallons (400 L)
- 3-year warranty
- Sound-dampening impeller design for 8 to 15% quieter operation
- Re-engineered efficient priming system for easier starting
2 Sunsun 4-Stage Canister Filter with 9-watt UV Sterilizer
The Sunsun 4-Stage Canister filter has three stages of water filtration plus an ultraviolet disinfection stage. The Sunsun filter contains three filter media baskets that hold foam filter pads, activated carbon and biological filtration media. The canister has a square shape design.
The Sunsun filter includes fine and coarse filter pads to remove particulate matter. It comes with one pound of pelletized activated carbon in a flow-through pouch. For biological filtration, the kit comes with one pound of porous ceramic rings. Sunsun even provides plastic biological filtration balls as an optional filter media.
The fourth stage of filtration is the 9-watt ultraviolet (UV) light. The UV light kills algae cells as they pass through the filter. The UV prevents algae blooms and keeps the aquarium water clear. The UV light also kills pathogenic bacteria and parasites the cause fish diseases.
The Sunsun 4-stage canister filter has a priming button making it easy to prime and start the filter. Just press the priming button to start the siphon that fills the canister. Once the canister if full of water, just plug it in. The filter begins working immediately. No more messy priming with spills!
- Rated for aquariums up to 150 gallons
- Quick-disconnect valve for easy maintenance
- Includes activated carbon and foam pads
- Comes with multiple layers of filter foam
- Uses 35 watts of electricity
3 Fluval FX6 canister filter
The Fluval FX6 canister filter is a large, heavy-duty aquarium filter. This Italian-made, state-of-the-art design has advanced features not found on other canister filters. If you’ve got a large aquarium or dirty fish, this may be your dream filter.
The filter uses a round basket-in-a-basket design. The media baskets stack on top of one another like other canister filters but that’s where similarities end. The FX6 baskets each have an outer chamber and an inner chamber. All the baskets stack together. The aquarium water flows through each chamber of the baskets.
The FX6 has six stages of filtration. The first stage uses FX pads which remove large debris. FX Bio-Foam pads remove fine particles and polish the water. Biomax filter rings are fired ceramic rings with internal pores for beneficial bacteria. Pre-cut FX carbon coated foam pads are specially shaped to fit in the round basket. The carbon filters remove odors, colors and dissolved organic contaminants.
The Fluval FX6 uses patented Smart Pump technology. The pump automatically primes and starts the filter. The smart flow monitoring system automatically adjusts the pump to maintain a consistent flow rate. The digital sensors purge the canister of trapped air bubbles once every 12 hours. This prevents annoying air locks that can shut the filter down when you least expect it.
- Rated for aquariums up to 400 gallons
- Maximum flow rate of 563 gallons per hour
- Holds lots of filter media
- Digital motor monitoring and control
- Automatic purging of air
4 Hydor 250 Professional Canister Filter
This Hydor Professional canister filter uses the square shape design as found on other canister filters. The motor lid is held on by two large, wide clips. Rubber feet on the bottom of the canister reduce vibration noise and keep the filter in place. The water pump uses a ceramic pump shaft. This ensures smooth, quiet operation.
The filter comes with long, kink-free tubing for easy routing behind the aquarium cabinet. The Hydor Professional includes a spray bar attachment for aerating the water. Spray bars are not available on all brands of canister filters, so this is a plus! The water intake and spray bar are held in- with suction cups. The intake tube is telescopic, meaning it can be adjusted to different depths.
Hydor included a push-button priming system to make start-up easier. Without the priming option, you’ll have to start the flow of water into the canister manually. Just give the primer button a push and the tank fills with aquarium water. Air is pushed out as water fills the tank. Just plug in the power cord to start the filter.
For easy maintenance, the filter comes with quick disconnect valves. Unlike budget valves, the Hydor uses ball-valves for leak-free reliability. The Hydor Professional canister filter comes with pre-cut mechanical filter pads that fit inside the baskets. The filter also comes with biological filtration media.
- Rated for 40-75-gallon aquariums
- Easy priming feature
- Can be used with other Hydor filter media
5 Penn Plax Cascade 1500 Canister Filter
The Penn Plax Cascade 1500 model uses five plastic media baskets, stacked inside the canister. Pre-cut coarse sponge and fine filter pads capture floating debris and water-clouding particles. A flow-through bag of ceramic bio-filtration media is included. A pouch of granular activated carbon also comes with the filter kit. The Cascade 1500 provides multiple stages of filtration using PennPlax media or you can use your own.
Rotating, quick disconnect valves make it easy to bring the canister to the sink for cleaning. The Cascade’s valves rotate 360 degrees, making it easy to route tubing from the tank to the canister. The outflow valve can be used to reduce the flow rate during feeding. This will prevent food from being sucked into the filter.
Maintenance is simple and quick. Just unplug the motor, close the valves and carry the filter to the sink. The nesting baskets have a handle for simplified media changes. The PennPlax media drops right into the baskets. No cutting or filling media bags.
The Penn Plax Cascade 1500 has a one-push priming button. Just pump the button once to fill the canister with water. Four locking clamps hold the lid tightly to the canister tank. The filter includes tubing, inlet and outlet pipe, spray bar and a directional nozzle.
- 350 GPH flow rate
- Recommended for aquariums up to 200 gallons
- 5 large media baskets
- Uses PennPlax pre-cut pads or your favorite media
6 Hydor 600 Professional Canister Filter
The model 600 Hydor filter has many of the same design features of the smaller 250 model. It’s rated for 90 to 150-gallon aquariums. The filter canister is taller, measuring 23.6 inches tall. Be sure this tall filter will fit under your aquarium cabinet!
The taller 600 model holds more filtration media. There’s plenty of room to add more filter pads to the baskets, polishing the water to crystal clarity. More baskets mean more activated carbon, ammonia remover and other specialty filter media can be loaded into the filter. Speaking of filter media, look at what comes with the filter.
The Hydor 600 uses five filter media baskets. The filter comes with filter pads that capture fine particles that cloud the water. Foam sponge filter pads capture larger debris. These can be rinsed and reused again. Ceramic biological filtration rings are supplied in a flow-through bag.
The Hydro 600 Professional Canister filter has a larger-capacity motor. Water flow capacity is 345 gallons per hour. This gives the Hydor filter the 90 to 150-gallon tank rating. In real life use, the filter is probably limited to aquariums up to 100 gallons.
- Rated for 90-150-gallon aquariums
- Comes with biological filter media
- Powerful flow rate
- Automatic priming button
7 EHEIM Classic External Canister Filter with Media
Eheim is a German aquarium filter company famous for high quality products. The Eheim Classic external canister aquarium filter is a basic design compared to other Eheim models. But that doesn’t mean you ignore this workhorse of an aquarium filter! Look what the Eheim Classic canister filter has to offer.
The Classic does not use media baskets. Instead, filtration pads and granular media are placed directly inside the canister tank. For over twenty years this design has proven simple and effective even for the most demanding aquarists. Take a look at the media choices for the Eheim Classic.
For mechanical particulate removal, Eheim MECH mechanical filter media is included with the filter. You can rinse this media and use it for many years. The Classic canister comes with Eheim SubstratPro, which is a granular media designed for beneficial bacteria (ammonia and nitrite removal). Activated carbon filter pads are not included but can be purchased separately. The Eheim Classic comes with high-quality accessories.
The Eheim Classic canister filter comes with a pair flexible hoses, a spray bar, and an inlet pipe. Eheim is famous for flexible tubing and outstanding suction cups for mounting the hose system in the aquarium. The filter uses two-piece shut-off valves that make cleaning the filter easy.
- Rated for aquariums up to 95 gallons.
- Super-flexible silicone tubing
- Precision plastic components won’t crack or leak
8 AquaTop CF Canister Filter
The AquaTop CF canister filter (525 GPH model) is a traditional canister filter with a twist. It combines multiple stages of filtration with a powerful ultraviolet light, all in one filter. The AquaTop CF filter has a push-button priming system. A quick press of the button starts a siphon, filling the filter tank with water. This feature-rich aquarium filter is worth a closer look.
Like other filters we reviewed, the AquaTop CF uses a quick-disconnect shut-off valve. The hose barbs have easy to use nuts to secure the hoses. The barbs even rotate to make hose routing easy. Speaking of hoses, the AquaTop canister filter comes with long hoses, giving you plenty of room to set up the filter under your aquarium.
The AquaTop CF canister filter has four baskets, that nest together. Each basket has a handle for easy stacking and cleaning. You have the option of using AquaTop filter media or your favorite brand of activated carbon, resin blend, phosphate remover or biological filter media. Check out the AquaTop media included with the CF canister filter.
The CF canister filter comes with one coarse sponge filter pad to pre-filter larger particles. Three fine micro-filtration pads are included for water polishing and extra-fine particulate removal. AquaTop also provides activated carbon, ceramic rings and plastic biological filtration balls.
The final stage of filtration is UV sterilization. The AquaTop CF has a 9-watt ultraviolet (UV) light inside the canister. The UV light kills algae cells in the water. The UV maintains clear water by inhibiting “green water” algae blooms.
- Long hoses for easy installation and maintenance
- Rated for aquariums up to 175 gallons
- Includes spray bar
- Filter media included
9 Marineland Magniflow Canister Filter
The Magniflow model 360 canister filter is rated for aquariums up to 100 gallons. It uses the square canister design with Stack-N-Flo filter trays. The Magniflow range of canister filters have a quick prime button that makes start-up easy. No more sucking on a hose to start the filter! But there’s more!
The Magniflow canister filter is constructed of high-quality plastic that won’t warp or flex. This means the lid seals properly to the canister, eliminating leaks caused by inferior plastics. A premium O-ring is used to seal the canister closed. This is important because flimsy O-rings gradually lose their ability to prevent leaks. The quick release valve block immediately shuts off the water flow and separates the hoses from the canister for spill-free filter maintenance.
There’s plenty of filter media included with the filter! The canister comes with two foam filter pads to screen out dirt and debris. You’ll also get Black Diamond activated carbon comes in a flow-through pouch. Next comes a combination of ceramic rings and plastic bio-balls to keep the water ammonia and nitrite-free. The last stage is a fine filter pad that polishes the water, ensuring crystal-clear water. Want more features?
The Marineland Magniflow 360 comes with long, kink-free tubing, inlet and outlet pipes, suction cups and nozzle. It’s easy to set up and get running. The Magniflow 360 comes with everything you need.
- Solid construction
- Long tubing
- Pre-cut and bagged filter media available
10 API Filstar XP Large Canister Filter
The API Filstar canister filter range has lots of unique features. The Filstar has a patented quick disconnect valve. A flip of the lever shuts off water flow and disconnects the hoses from the canister. Built-in handles make it easy to carry the canister to the sink for cleaning. Soft, rubber feet dampen vibrations for near-silent operation. But what about filter media?
XP filters come with two types of foam pads. The coarse foam pad (20 pores per inch), removes large particles. The fine foam pad (30 pores per inch) removes tiny particulates. XP filters also come with Bio-Chem Zorb, a blend of premium activated carbon and adsorption resins. Bio-Chem Stars are biological filtration media made of porous plastic. The Stars have a 50-micron pore network, providing a protective environment for beneficial bacteria. A final polishing filter pad that makes the water sparkling clear.
The API XP canister filter comes with six-foot silicone hoses for easy routing behind the aquarium. The inlet and outlet fittings are sturdy and are attached to the tank with suction cups. There is no spray bar option.
- Drip-free quick-disconnect valve
- Heavy-duty media baskets
- Quiet operation
- Made of premium plastics that won’t warp
Best Canister Filters for Aquariums Buying Guide
What To Look For When Selecting An Aquarium Canister Filter
Tips for selecting the best aquarium canister filter
The first thing you need to know is that canister ratings are exaggerated! A canister rated for a 100-gallon aquarium might be adequate if the aquarium contains a few fish and gets frequent water changes. In reality, this canister filter is best suited for a 55 to 75-gallon aquarium. Filter manufactures often try to gain market share by inflating gallons treated specs. Want to know the truth about flow rates?
The filter flow rates, provided in gallons per hour (GPH) and liters per hour (LPH), are based on using the canister filter with no filter media in it. This is an industry standard, but it can be misleading to aquarists comparing filter specifications. Some filter manufacturers provide a flow chart showing actual flow rates based on how high the water is being pumped to the aquarium. The taller the tank, the lower the flow rate per hour. Now you’re ready to look at types of filtration.
There are three types of aquarium filter media. Mechanical filter media removes solid particles that float in the aquarium water. The particles include organic matter like uneaten food, aquarium gravel dust, aquatic plant fragments and suspended algae that cause “green water”. Mechanical filtration is always the first media in the canister filter. It’s designed to remove debris, so the other filtration materials don’t get coated with gunk. Foam pads are the most common form of mechanical filter media. Look for:
Chemical filtration media removes ammonia, nitrite and nitrate and dissolved organic compounds that discolor the water. Ammonia is a toxin released by fish as a waste product. Ammonia-removing zeolite media will remove ammonia in freshwater. Dissolved organics produce a yellow color in aquarium water. Activated carbon adsorbs organics, keeping the water clean and clear. Here’s the media you can use in a canister filter.
Biological filtration is the natural process that converts toxic ammonia into nitrite (also toxic) and nitrite into harmless nitrate. It occurs in all aquariums. Biological filtration is performed by beneficial “nitrifying” bacteria. Nitrifying bacteria attach to solid surfaces like gravel, plastic plants, live plants and on filter surfaces. Canister filters usually come with one or two kinds of biological filtration media. The idea is to provide more surface area for the bacteria to attach to. Biological filter media comes in several forms.
Some filters have an ultraviolet light built into the canister. The feature is called UV sterilization, but it is not exactly correct. The low-wattage UV bulb won’t sterilize the aquarium. The UV light won’t do much to control bacteria and parasites that cause fish diseases. The light is not powerful enough to make a significant difference on these microbes living in the aquarium and on the fish. The good news is UV lights will kill algae cells that pass through the filter. They’ll help keep the water clear.
Now that you know the basics, we can reveal some canister secrets. Here’s what you need to consider when choose a canister filter.
How Does A Canister Work?
Taking The Mystery Out Of Canister Filter
The idea behind a canister filter is to pump aquarium water through a series of specialized filtration media. Unlike hang-on-back (HOB) power filters, canister filters hold a lot more media. The canister is used to contain the filter media while water passes through it. Dirty water flows by gravity from the aquarium and into the canister. The water pump motor is molded into the lid of the filter. The pump pushes the filtered water back to the aquarium. Aquarium water leaving the canister filter should be cleaner than the water entering it.
The canister lid is seated onto the canister tank and held secure by clamps. The lid uses an O-ring to seal the water in and air out of the canister. The shut-off valves prevent water in the aquarium from back-siphoning when the tubing is removed from the canister. It also helps when disconnecting the filter for cleaning. You won’t lose the siphon. This is a major improvement from earlier canister designs.
Canister filter models come in various sizes and the flow rates. Larger filters require higher flow rates to handle the needs of big aquariums. That’s why manufacturers rate their filters by gallons per hour and aquarium size.
Aeration is important in freshwater and marine aquariums. Oxygen enters aquarium water through surface agitation. Carbon dioxide gas leaves the water at the surface. All canister filters use some style of water return outlet to stir up the water surface. Spray bars and nozzles are the most common options. Water movement diffuses excess carbon dioxide and increase oxygenation of the water.