Best Canister Filters – Buyer’s Guide

Selecting the best canister filter for your aquarium is a very important decision because it will affect the quantity and type of fish and plants you will keep in the aquarium. In addition, it will also affect the level of maintenance that the aquarium will need.


The filters are here to keep the water clean and free of impurities like food leftovers, rotten plant material, waste products, toxins and more. Thanks to the rapid advancements in the field of technology, aquarium equipment manufacturers have managed to design different types of filters. We’re here to help you find the best canister filter for your aquarium!

What are the Best Canister Filters?

  1. Fluval 406
  2. Penn Plax Cascade – Popular Choice
  3. Hydor Professional
  4. Marineland Magniflow
  5. SunSun – UV Sterilizer Canister Filter
  6. Fluval Fx6 – Best for Big Aquariums

If you have a smaller fish tank (or larger), our selections have other sizes for you to choose from. If you have trouble making a selection feel free to ask for help by dropping a comment below.

1. Fluval Canister Filter

Currently on Sale
Fluval Canister Filter for Aquariums - 406 - 100 Gallon
  • Multi-stage filtration for healthy fresh &...
  • Suitable for aquariums up to 100 gallons. Flow...
  • Sound dampening impeller design for a quieter...

After the initial success with their 405 model, the management of Fluval decided to create a 406 model. The best part is that they have managed to keep all the great features of the previous model, add a few new ones and upgrade some of the existing ones. For instance, we can all agree that this Fluval External Filter provides much better filtration. In addition, it offers easier priming, setup, and maintenance too.

The cleaning process is simpler too and this was one of the main problems in the past. This filter is perfect for large aquariums of up to one hundred gallons. Keep in mind that this external fish tank filter doesn’t have a spray bar, but you can always buy one and add it to the system later. Definitely one of the best canister filters on the market, we highly recommend you at least take a look at it!

  • An improved version of another successful filter
  • Very quiet operation
  • 3-year warranty
  • A wide range of filtration media
  • Made of premium-quality materials
  • No spray bar included

2. Penn Plax Cascade Canister Aquarium Filter

Currently on Sale
Penn Plax Cascade Canister Aquarium Filter (Cascade Black 1500...
  • Cascade 1500 Black Elite Kit. Handles up to 200...
  • Over $50 of added value. Includes new black...
  • All parts and replacement media is OEM from Penn...

Penn Plax is one of the oldest companies focused on the production of pet equipment. They have already sold thousands of canister filters, but it seems that this Cascade Canister Aquarium Filter is easily one of their best canister filters. They have varieties that support filtration in aquariums with different sizes so check the label. This specific canister filter delivers heavy duty filtration and made from quality materials. The most powerful version of the Penn Plax Cascade Canister Aquarium Filter can process 265 gallons in just one hour. What’s even better is that the price of this filter is budget friendly.

  • Very durable
  • Tip-proof base
  • Low price
  • Almost noiseless
  • Uses slightly more power than your average filter

3. Hydor Professional Canister Filter

Currently on Sale
Hydor Professional 600 External Canister Filter, 90-150 gal, 345...
  • The hydor professional 600 Aquarium External...
  • All the biological, mechanical and chemical...
  • From the easy priming feature to the telescopic...

Thanks to Hydor you can now get a professional-grade canister filter at an incredibly low price. With over 30 years of experience in this industry, it is quite natural for Hydor to come up with some unique and efficient solutions when it comes to filtering. It is good to know that this actually the first canister filter made by Hydor and the results it provides are even better than expected. It has a compact rectangular shape form and it can use the relatively large amount of filtration media. This is a soundproof filter with an extremely efficient motor which includes the latest technology.

  • Promises excellent return on investment
  • Simple priming system
  • Simple to install
  • Excellent flow rate
  • Adjustable spray bar
  • The instruction manual isn’t very detailed

4. Marineland Magniflow Canister Filter

MarineLand Magniflow Canister Filter for Aquariums
  • Canister lids ensures water tight seal
  • The polishing filter pad acts as a water polisher...
  • The bio-filter balls and ceramic rings provide a...

In case you are looking for a canister filter that doesn’t need much maintenance and has a reasonable price, then you should put Marineland Magniflow Canister Filter on your list. This filter is actually an improved version of their previous C-Series filter. It comes with a capacity that makes it good even for 100-gallon aquariums. This specific model comes with a huge media capacity of about 3.4 gallons. This makes the Magniflow Canister Filter one of the biggest in this class. However, users must be careful and avoid overfilling. The package comes with carbon filter bag, bio-filter balls, filter foam, polishing floss pad, tubing, and ceramic-based bio-filter rings.

  • Processes 360 gallons per hour
  • Made by a reputable company with excellent customer service
  • Comes with four trays for better filter media use
  • Bulky – if this doesn’t matter to you this is a solid filter

5. SunSun HW-304B Canister Filter with UV Sterilizer – Best Filter for Algae

Sunsun Hw304B 525GPH Pro Canister Filter Kit with 9-watt UV...
  • HW-304B Pro Filtration Kit, Good for up to 150...
  • Flow rate: 525 GPH (2000L/Hr)
  • Dimension: 11" L X 11" W X 17" H

Now here’s an example of an efficient canister filter that is made from a relatively unknown company. This company has been on the market for a couple of years now, if they keep making such products they will become popular worldwide. Even though we are talking about an inexpensive filter, the fact is that the Flexzion SunSun HW-302 Canister Filter can make the water in your aquarium perfectly clean. The filter can also process large amounts of water and it is barely visible. This is the best canister filter on a budget if you have an aquarium that is smaller than 75 gallons.

  • Low price
  • Processes 365 gallons per hour
  • Very quiet
  • Three separate media trays
  • Relatively small
  • Has a UV sterilizer
  • Poor instructions provided

What You Should Know Before Buying a Canister Filter

Well, I hope you agree with this list as much as I do. This might not suit you, so we prefer you to have a look at all of the details below. That will help you in choosing the best canister filter possible.

What is a Canister Filter?


Canister filters are units that work under strong pressure making them one the best aquarium filters. They are usually mounted under the aquarium and conduct all three forms of filtration. In other words, with their help, you will get complete filtration. It’s also worth mentioning that they come in two different sub-types – a complete canister filter which comes with an independent pump and a modular canister filter that needs an additional pump. The latter is especially helpful when used together with other types of filters like the wet/dry filter.

On the other hand, complete canister filters rely on –tubes for water intake and a spray bar for the return of the water. When the canister filter is mounted on the aquarium, a siphon is activated. This siphon allows the water to circulate from the aquarium to the filter. So, the water will first enter the filter and go through a mechanical media and reach the chemical media. Once the chemical filtration is finished, the water goes to the final chamber that has the biological media and this is where the nitrogen cycle is finished.

Benefits of a Canister Filter

There are many pros and cons related to this type of filter but it seems that the number of advantages is much higher. First of all, a canister filter can significantly increase the total volume of water in the aquarium system. Without any doubt, this is a positive thing due to the fact that increased water volume leads to lower concentration of dangerous impurities like waste and food leftovers.

In addition, a bigger volume also leads to increased stability of water with fewer fluctuations in terms of water parameters in general and temperature too. Another great thing about canister filters is that the fish will get more space because they are attached to the bottom of the aquarium. Additionally, the aquarium will look more natural and more attractive because this filtration system is less visible. The presence of a rainbar allows the filter to aerate the aquarium water too.

Canister Filter Drawbacks

Of course, there are some cons linked to canister filter too. For example, they require proper and regular maintenance. This is the main reason why so many canister filter users give up on them after a while leaving them clogged and dirty which is obviously the worst solution. So, if you are planning on using a canister filter, you better be prepared to clean and maintain it regularly. According to some experts, it’s not very difficult to establish a routine like this and even though it might look a little bit time-consuming in the beginning you will reduce the time needed for this activity after a while.

How Do Canister Filters Work?

We have already explained the basic process, but let’s go into details. The filtration process in the canister filter starts with the mechanical filtration which is probably the best among all types of aquarium filters. This is a pressurized filter which means that the water is practically forced through a refined material that can keep even the tiniest impurities. Some of these products have clear indicators about the size of particles that the canister filter can process, so take a good look at them.

The next step is the chemical filtration which is once again very efficient. Once again, the reason is simple – the pressurized unit promises better results compared to other filters. In addition, users should know that it is quite easy and simple to change the kinds of chemical filtration media used in canister filters. Experts suggest the use of activated carbon even though there are some other highly efficient types of media too.

Finally, the process ends with the biological filtration. The results that canister filters provide at this stage are mediocre because of the amount of oxygen found in the passing water. The lack of water to air contact caused by the pressurized media is the main reason for this. The good news is that there is more than one type of media used in these filters for biological filtration and some of them might be more efficient than the others. For instance, the porous materials, ceramic rings and engineered glass materials used for this purpose.

Setting up a Canister Filter

Start by putting the output and input flow pipes on the aquarium exactly where the filter will be attached. There are cases when people need a spray bar or a directional output that should be used on the output pipe for this purpose. If there is a pre-filter, snap it onto the input pipe’s end.

Next, put the canister in its position and check the length between the output and input pipes and the ports. Use a knife or scissors to cut the hose. Choose a length that is a little bit longer than the length you’ve measured just in case.

After that, attach the ends of the hose adequately – to the output and to the input port of the canister. The filter basket/s must be filled with the media used in your specific canister filter.

Put the filter basket inside the canister in the right direction. Don’t force the basket in, make sure it fits well. Fill the canister with the recommended fill level with aged aquarium water or dechlorinated water that comes from the same aquarium.

Put the big O-ring in the water and make sure it’s wet. After that, put the ring around the upper part of the canister. Turn the device on and watch the process if you want. When you are using it for the first time, check the device for leaks.

Canister Filter Maintenance

The number of canister filter models is increasing every year and this is definitely something that we should take into account when we are discussing canister filter maintenance. The brand and the model of your canister filter, as well as the number and type of filter media used in it, will determine the maintenance process.

However, generally speaking, freshwater canister filters allow users to opt for many different filter media options. Many of these filters come equipped with cartridges, baskets, media bags and even with separate chambers where you can place your desired media and get the specific type of filtration you are looking for. There are some filter media that must be cleaned on a regular basis, while other media varieties must be replaced. It is a smart idea to check the recommendations provided by the manufacturer in order to avoid any mistakes.

We have already mentioned before that cleaning and maintaining canister filters requires more time and effort in comparison to most aquarium filters. When you are cleaning this filter, you must put your focus on the canister and the hoses and the impeller too. It is a smart idea to use a brush with soft bristles to scrub the hoses and the impeller because these parts of the filter are usually gentle and fragile. Before you reassemble the parts of the canister filter, it’s the best idea to ensure that every part is perfectly clean. If the cleaning you’ve performed is not complete, you can expect leaks.


What is the Best Canister Filter for Big Aquariums?

The canister filters listed here are great choices for your average fish tank but for larger aquariums you may need to invest into something a bit more powerful. Like the FX6 Fluval Canister filter. It’s able to filter up to 563 gallons of water per hour! Perfect for aquariums up to 400 gallons.

Currently on Sale
Fluval Canister Filter, FX6 Filter (400 Gal)
  • Multi-Stage Filter that produces healthy aquarium...
  • Features Smart Pump Technology for optimal filter...
  • Self-starting filter-just add water and plug in....

What’s the Best Canister Filter Media?

The best canister filter media we highly recommend is purigen, along with mechanical filtration and biological filtration of course. It does an excellent job at keeping your nitrate levels at 0ppm or close to it. It also keeps your water crystal clear and lasts several months!

How Do You Prime a Canister Filter?

The best way to prime a canister filter is by filling it with water before plugging it in. This way prevents the motor from overheating.

Canister Filters vs. Other Fish Tank Filters

As we have already mentioned, there are many different types of aquarium filters out there, so one might ask why they should choose canister filters over others. This is a legitimate question and the best part about it is that canister filters are not always the best choice. However, there are many situations in which these filters are more than useful.

Canister filters reign supreme in mechanical and chemical filtration. Regardless of the lack in biological filtration, canister filters are great for saltwater, freshwater tanks, for reef tanks, and turtle tanks. The compatibility of canister filters is what make canister filters highly popular by many people.

Furthermore, you should take the price into consideration too. Canister filters belong to the group of aquarium filters that can be quite expensive like hob filters for example. They are also more expensive compared to all internal filters, but the truth that internal filters are not very efficient. So, it is quite logical for a product that is very efficient and what it does like canister filters processing aquarium water to be expensive.

Taking care of a canister filter requires more time and effort compared to power filters, dry/wet filters, and under-gravel filters. So, unless you are prepared to follow the strict rules of maintenance associated with this type of filters, you should look for another solution.

You should also think about the size of the aquarium. There are canister filters designed to work in large aquariums and small aquariums. The same goes for the rest of the aquarium filters found on the market.


Canister filters are one of the most popular types of aquarium filters today. They are extremely efficient, but only when they are maintained and used in the right way. A high-quality canister filter of this kind will provide a benefit of choosing the type of filtration adequate for your aquarium by letting you adjust the filter media. The other types of filters usually require the use of pre-designed and pre-made media. While it is true that canister filters require regular maintenance, the need for maintenance is much lower compared to power filters.

Keep in mind that when it comes to canister filters, just like when it comes to most aquarium filters, you must replace carbon in them regularly and frequently because the carbon – if saturated and not replaced after a long time can release the toxins it absorbs. Canister filters have proven to be excellent for medium and large tanks because they can process large amounts of water quickly. These filters provide excellent chemical and mechanical filtration and decent biological filtration.

When choosing a canister filter for your aquarium, look for products made by reputable companies. The models in this guide are used by thousands of people around the globe.

Last update on 2019-05-19 at 20:35 / Affiliate links / Images from Amazon Product Advertising API

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