Guide to Aquarium Canister Filters

Kowing How to Use Canister Filters, the Pros and Cons of Different Models

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Canister filters use a plastic box (canister) to hold trays of different filter media. Water is pulled out of the aquarium through tubing by an electric pump and pushed through the filter media trays, then back into the aquarium through another tube. The canister is usually placed in the stand under the aquarium. A canister filter is an ideal choice for tanks 40 gallons or larger, especially for show tanks, as it can be completely concealed and not detract from the appearance of the aquarium. Because canister filters use a pump to force the water through the filter media, they are particularly good at removing particulate matter. Canister filters are adaptable to a variety of conditions.

By changing the type and volume of various media, it is possible to create a custom filtration system for the needs of your aquarium. Water can be polished using diatomic sleeves, extra rings or sponges can be added to encourage bacterial colonization for increased biological filtration, or additional mechanical media can be used for aquariums that have a lot of particulate waste. Chemical filtration can be done using activated carbon to remove chlorine from the water, or by using special resins to remove other dangerous toxins.

  • 01 of 05

    Eheim Classic

    Green Eheim classic canister.

    Boasting a high throughput rate and durability, the Eheim is the quietest canister on the market. It features a compact design and easy-to-handle latches. The classic series has been on the market for years and has performed reliably. Replacement parts are easy to find, which is a big plus. Perhaps the only issue is that this series lacks self-priming (doesn't start water flow through the filter automatically). However, it does provide tips on how to prime the filter, and it isn't too difficult. Although somewhat pricier than other brands, many times Eheim will outperform others. It's definitely a solid product. All models include spray bar, inlet pipe, hose and installation accessories

    The Eheim Classic series filters are guaranteed for two years.

    Classic Models include:

    • 150: for aquariums sizes 50-150 Liters (12-37 gallons)
    • 250: for aquariums sizes 80-250 L (20-63 gal)
    • 350: for aquariums sizes 120-350 L (30-87 gal)
    • 600: for aquariums sizes 180-600 L (45-150 gal)
    • 1500XL: for aquariums sizes 300-1500 L (75-375 gal)
  • 02 of 05

    Fluval 05 Series

    Black Fluval canister filter for an aquarium.

    Fluval produces one of the most economical, yet efficient, multimedia filters available. Learning a lesson from its older models that were too tall and unwieldy to service, the redesigned models are compact and sport larger latches similar to the Eheim products. Self-priming has been added, which is a big improvement over previous models. However, they still tend to be noisy if not properly filled. In spite of that, you can't go wrong with a Fluval.

    Fluval canister filter features:

    • Square-shaped canister design holds 35-50% more water than round canisters of similar size
    • Improved motor performance – reduces maintenance frequency, increases flow rates and head pressure
    • Sound-dampening impeller offers 8-15% quieter operation than previous generation
    • Patented Aqua-Stop valves for easy hose disconnections
    • Redesigned impeller cover for added durability
    • Re-engineered priming system for easier start-up
    • Filter media included – mechanical, chemical and biological

    Models include:

    • 106: for aquariums sizes up to 100 L (25 gal)
    • 206: for aquariums sizes up to 200 L (45 gal)​
    • 306: for aquariums sizes up to 300 L (70 gal)​
    • 406: for aquariums sizes up to 400 L (100 gal)​
    • 107: for aquariums sizes up to 130 L (30 gal)​
    • 207: for aquariums sizes up to 220 L (55 gal)​
    • FX4: for aquariums sizes up to 1000 L (250 gal)​
    • FX6: for aquariums sizes up to 1500 L (400 gal)​
  • 03 of 05

    HOT Magnum

    Magnum filter for an aquarium.

    The Marineland HOT (Hang On Tank) Magnum filter balances price with some of the best features in a canister. It is self-priming, quiet, and offers convertible filtration modes, including the option of adding a matching Bio-wheel system for increased biological filtration, as well as a diatomic sleeve to remove even the smallest particles from the water. The clear canister makes it easy to see the condition of the filter. Optional gravel cleaner is a nice perk to an all-around great package. The fact that it is a canister filter that hangs on the outside of the tank, like a power filter, makes it a unique form of filter.

    Between the HOT Magnum and HOT Magnum Pro, the main difference is the addition of a Bio-wheel system to the Pro system. Both are rated at 250 gallons per hour, for tanks up to 50 gallons.

  • 04 of 05

    Rapids Mini Canister Filter

    Rapids mini canister filter for an aquarium.

    For those looking to have the perks of a canister filter on a smaller tank, the Rapids Mini canister filter is a great option. With a flow rate of 80 gallons per hour, it is suitable for aquariums up to 20 gallons. It comes with a spray bar and directional flow diffuser. Warrantied for two years, this filter is a good option for ​a small tank, particularly the Nano tanks.

    Continue to 5 of 5 below.
  • 05 of 05

    API FilStar Canister Filter

    Rena FilStar canister filter for an aquarium.

    Although less well known than other canisters, the API FilStar has many of the same features. It is designed with self-priming and quick disconnect features to allow safe and easy stop and start of the filtration when maintenance is needed, an anti-airlock system to prevent unexpected filtration stops, and anti-noise feature to prevent vibration against cabinet/floor. The self-locking water shutoff system is a nice touch, and the price is very competitive with other canister filters of the same size.

    FilStars carry a warranty for two years.

    Currently offered models include:

    • Filstar XP S: It has a flow of 250 gallons per hour and tanks up to 45 gallons.
    • Filstar XP M: It has a flow of 300 gallons per hour and tanks up to 75 gallons.
    • Filstar XP L: It has a flow of 350 gallons per hour and tanks up to 175 gallons.
    • Filstar XP XL: It has a flow of 450 gallons per hour and tanks up to 260 gallons.