Stephen is an owner of several aquarium supplies shops in New York. Like no one else, he knows how to pick the perfect fish tank or any aquarium accessory from pump to artificial decorative plants.
Last updated: August 22, 2022
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A good filter is essential for a clean and healthy fish tank, but many people are wary about complicated cleaning and confusing filtration media. This is where a nano canister filter can help.
In our quest to find the best nano canister filter, we’ve looked at the filtration types and flow rate, which will determine the functionality of the unit for your tank needs. We’ve also considered the mounting types, which can impact the aesthetics of your tank. After all, you want to look at your fish, not a filter unit obscuring the tank. Finally, we consider the ease of use, including cleaning and priming. All of these considerations have helped us to discover the best choices at a variety of price points.
Other features: self-priming, 6 months warranty, quiet operation
The Finnex PX-360 is a 3-stage unit, which can filter a 25 gallon tank up to almost four times per hour. It’s small, easy to mount on the rear of your aquarium and it’s surprisingly quiet when operating. The housing is well built and durable and it has a built-in spray bar to aerate and oxygenate the water efficiently.
This is an ideal filter for aquarium owners that have a 10-25 gallon tank. Due to the smaller dimensions, this filter is a great choice if you don’t want to waste valuable space inside and outside the aquarium. This is one of the best small canister filters on the market and that’s why it’s the editor’s choice.
What stands out?
What we loved most about this filter was the high capacity which can clean up to 95 gallons per hour. We liked the design of the media trays, they can be opened separately for media changes and they are easy to clean. It was nice to see intake and outtake tubes that are efficient and durable.
What cons did we manage to find?
What needs attention is that this filter would be much better with an upgraded impeller. Another drawback is that this unit must be primed before you can use it in your aquarium. The filter must be kept in an upright position and any lateral movement causes an air bleed that will cause a water leak. The seals must be lubed to prevent leaks and the supplied instructions are hard to understand.
Other features: integrated heater, self-priming, adjustable flow control
The OASE Indoor Aquatics Filtosmart Thermo is a compact filter with a built-in 2-stage filter. This unit has both mechanical and biological filtration with a sufficiently large surface to encourage the colonization of beneficial bacteria in the tank. This filter is self-primed for a quick and easy start up and it’s quiet during operation.
This is an ideal external filter for people with an aquarium up to 30 gallons in size. It’s an ideal choice for both fresh and salt-water applications and the built-in heater allows the user to make precise temperature adjustments. Users that want an unobstructed view of their tank will also appreciate the compact and unobtrusive design.
What do we love it for?
What we liked most about this filter was the large filter surface, which is housed in a compact unit. The built-in heater works well and the inlet and outlet flow is fully adjustable. The maintenance is clean and efficient because the locking features are integrated in the inlet and outlet connections. This is a well-built product that comes with a lot of accessories and that’s why it’s our premium pick.
What were we disappointed with?
What could be better is that this is not a perfect filter. The hoses that are supplied with the unit don’t make a secure and watertight connection. Adding some plumbing tape to the screw threads helps, but this is not an ideal long-term solution. The 4 feet of supplied tubing is insufficient and we needed to upgrade all the tubes with a flexible and pliant alternative.
This is the successor to the Magnum 360 filter that many aquarium owners liked because the design was versatile. One of the drawbacks to the Magnum 360 was the limited media space and this has been addressed in this new model. This is a well built unit with improved seals, a stack and flow feature to prevent premature water flow, and a quick latch canister lid.
This is an ideal filter system if you want a faster and less messy cleaning experience. The quick release function shuts the water off immediately and it separates the motor for easy access. A handy stack and flow filter tray will prevent the water from flowing into the different filter stages until you are ready.
Why is it special?
What we liked most about the Marineland ML90749 Magniflow Canister Filter was the filtration media supplied with the unit. The mechanical filtration stage uses a dense and reusable foam to remove larger particulates. This is followed up with bio-balls for cleaning and a final stage adds extra polish to the water. The unit operates quietly and a 3-year warranty is included.
What are the flaws?
What we didn’t like about this filter is the lack of a diatom filtration option which was a final water polishing option on the Magnum 360. In our opinion, the water polishing stage should be placed before the bio-balls. This would keep the biological and chemical filtration media chambers cleaner for longer. Other limitations, include: no valve switches to adjust the water flow and a hard limit of 100 gallons.
The Aquaneat Mini Aquarium Filter is a small and convenient external canister filter for a nano or mini cube tank. There are four filter media stages, they are a white floss pad, a black sponge, ceramic rings, and bio-balls. These offer three separate filtration methods, mechanical, bio, and chemical filtration for cleaner water.
This filter system is ideal for users that want a unit that’s easy to install and simple to clean. It’s perfect for tanks up to 30 gallons, a flow control valve allows you to set your desired flow rate and this maxes out at 400L/h (105 gph). If you have specific filter media needs, it’s easy to replace the media in the bucket.
What do we love it for?
What we liked most about this unit is the sheer value for money that it offers. Despite the relatively low price you have everything you need to get up and running quickly. The inlet tube, outlet spray bar, hoses, and filter media are all supplied with the unit. Just make sure to remove the plastic bag that protects the ceramic rings in transit before you use the filter.
What were we disappointed with?
What we didn’t like about this canister filter is the build quality, which is certainly at the budget end of the Aquaneat range. Some reviews have reported that the unit fills flimsy and cheap. Additionally, some have had issues with electrical connections, which suggest that the materials may be a little too cheap for proper function.
Other features: permo-elastic silicon sealing ring, comes complete with filter media
This EHEIM Classic External Canister Filter is a smaller unit that can accommodate a tank 10 to 40 gallons in size. It’s a 3-stage filter unit with mechanical, chemical, and bio filtration media systems. The maximum flow rate is 79 gph which means that you can filter the water approximately 4 times per hour if you have a 20 gallon tank.
This is the perfect nano filter for small tanks. It’s easy to clean and the filter media changes are simple. The top of this canister filter is well sealed when the unit is running and the housing feels well built and durable. As an external nano filter, this won’t take up any space in a small tank which will improve your viewing experience.
What are our favorite features?
There are many areas where the EHEIM Classic External Canister Filter impressed us. The filter media supplied with the unit is high quality and you won’t need to change it for some time. There are plenty of accessories, including a mounting kit, intake and outtake tubes, a filter basket, and more. This unit is compact, it’s not mounted in the tank and it will not take up much shelf space.
What could be better?
What we didn’t like about this product is the installation. Although the fittings are supplied, you need to cut them to size and connect the hard plastic to soft silicone pipes. This can be tricky for a newbie and the manual isn’t much help. So, either the instructions need more work or it would be better if the tubes were easier to cut to size.
Keeping fish is a popular hobby for many people. In fact, according to PR Newswire, fish tanks can be found in 7.2 million homes in the US. With so many tanks and accessories, finding the best nano canister filter can be tricky. So, here we’ve compiled a buying guide with some answers to frequently asked questions to assist you.
Benefits of Canister Filters
A good filter is crucial to keeping your fish tank clean
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and healthy. Choosing the best canister filter for small aquarium is a sound investment but it’s important to understand the benefits before you commit to buying. A canister filter operates differently from a traditional unit that’s mounted on the rear of the tank. Let’s look at the major differences in more detail:
1. The High Water Flow Rate
There are differences between certain canister filter models but some do have better water flow rates. This makes them a good option for a tank that requires plenty of filtration. Most of the filters on our list such as the Finnex PX-360 have a spray bar included. This can be run across the surface of the water to aerate the tank and eliminate scum. A spray bar can remove the need for an air pump which can be a noisy distraction.
2. Filter Media Options
The media options for canister filters include carbon, phosphate removers, ammonia removers, chemi-pure, bio-balls and more
A good canister filter has a large volume of filtration media space in comparison to its overall size. And the best part is that you have the option to choose what filter media to use in your filter. Many people opt for carbon but there are other options, including phosphate removers, ammonia removers, chemi-pure, bio-balls and more. This flexible approach allows you to tailor your filtration requirements as needed.
3. Simple Setup and Easy Cleaning
In the past, setting up and cleaning a tank filter was an involved and messy process. The latest canister filter models such as the OASE Indoor Aquatics Filtosmart Thermo is a breeze to set up and clean. In many cases, you don’t need to prime the unit before using it in your tank. There may even be auto drain and shut-off systems to reduce the mess when cleaning.
Some of the best canister filters such as the Marineland ML90749 Magniflow Canister Filter have a generous 3-year warranty. Some of the best filters are built in Italy and Germany which are well known for the production of high-quality aquarium equipment. Even on a smaller budget, it is possible to get a reliable canister filter made in China and the reviews are your friend.
5. Noise Levels
This may be the biggest difference between canister filters and those units that are mounted on the rear of the tank. The main problem with traditional filter units is the vibrations they create in the tank and that rumble can be annoying. In comparison, a good canister filter is quiet and light sleepers should factor this into their final choice.
6. Aesthetic Considerations
Let’s face it, you want your aquarium to look nice, but there are practical considerations. If your tank has filter mounts and other components or tubes hanging off the side, it can be a problem in high traffic areas. The main component of any tank is the heater which is concealed inside many canister filter units. This reduces the clutter in and around the tank to improve your viewing experience and safety.
How to Pick the Best Canister Filter for Nano Aquarium
There is a wide variety of nano canister filters and accessories in the market today
When you’re shopping for the best nano canister filter, there is a wealth of options. So, here are some of the features to consider before making your final purchase decision.
Flow Rate and Capacity
The capacity and flow rate of your canister filter is extremely important and it must be carefully matched to your tank. If you have a 30-gallon tank, you need to ensure that you get a filter that is rated for that volume of water. The best way to think of the flow rate is that it’s the processing power of the filter.
As a rule of thumb, choose a filter that can process four or even five times the volume of water that your tank can hold every hour.
So, if you get a filter for the same 30-gallon tank, it should be capable of filtering 120 or 150 gph (gallons per hour). An adjustable flow rate is a handy feature, but it’s not as crucial for a smaller nano tank.
The type of filtration is important and the best canister filters are 3-stage units capable of mechanical, chemical, and biological filtration. Every filter on our list comes supplied with the required filtration media to get you up and running quickly. This should last a while, but you need to ensure that this filtration media is of a high quality. You may want to invest in a canister filter that has plenty of space to add different filtration media if you have specific requirements. If the media baskets are easy to access and there is enough space you can use many filtration media types in series.
Mounting and Size
Decide on where you are going to place the filter before choosing the size of it
Choosing the best canister filter for a nano aquarium is easier when you consider the size of the unit. The capacity and relative processing power of the unit will determine the overall size. But, you need to have a good idea of where you are going to place the canister filter. Many people place them on a nearby shelf and others prefer to hang them from the rear of their tank.
If you have a nano tank the better option is hanging it on the back because it’s easier to use and access is improved.
This can be hard to evaluate from the exterior, but you need a filter with a durable housing, a good impeller, and a reliable motor that won’t let you down. Each of these components is critical and research should reveal their various merits and flaws. If you purchase a filter and it breaks down a few months later it’s a waste of money. This is another reason to look at the warranty because this demonstrates the manufacturer’s confidence in their product.
Ease of Maintenance
You need easy access to the canister filter through a lid that seals firmly when the unit is operating. It should be easy to disconnect and connect components in the filter for cleaning. Many filters have built-in features to make this process less messy and these should be detailed in the owner’s manual.
Certain canister filter models need to be manually primed before you can use them in your aquarium. This can be a fiddly process, there may be some maneuvering and adjusting to even get the filter started! But, this is important. If you don’t prime these units correctly, they can overheat and this will burn out the motor. If you are a beginner, it’s a good idea to choose a filter that is either self or easy priming. These are handy features and it helps you to get up and running quickly with virtually no experience.
Choosing the biggest canister filter that you can afford is not necessarily the best approach. Although you cannot over filter a tank, it is possible to create too much current which can create detrimental effects.
This is a tricky question to answer because different manufacturers and models may have certain procedures that you need to follow carefully. However, there are a number of steps that most canister filter cleaning sessions will follow. First, turn off the filter, shut-off the valves, unscrew the tubes and bring the filter to a sink. Now you can remove the motor housing, the internal connections and get ready to clean. Start by removing the impeller, clean it and then remove the biological media trays. Clean the internal and external filter canister surfaces, reassemble the unit, turn the shut-off valves back on and restore power. For full detailed instructions for your canister filter refer to the owner’s manual that came with it.
As we’ve shown, there really are some great nana canister filters on the market today. From the versatile Marineland ML90749, which has improved on its predecessor, the Magnum 360 to offer a versatile unit that is both quick and easy to clean without creating mess, to the compact OASE Indoor Aquatics Filtosmart Thermo, which offers mechanical and biological filtration. However, the stand out pick as the best nano canister filter has to be our editor’s choice, the Finnex PX-360.
This impressive filter has three filtration stages, yet it is small enough to mount on the rear of an aquarium. It is ideal for tanks less than 25 gallons, but it has high-capacity filtration that can clean up to 95 gallons per hour. This filter also has nicely designed media trays that you can separately open to change the media, making them very easy to clean.
The Complete Guide to Cleaning Your Fish Tank (With New Tips for 2021)
Make cleaning your fish tank easy with this in-depth guide. Everything you need to know including how to, how often, and what tools you need.