Filters are important for our fish tank and they need good maintenance for better performance. The canister filter is one of the best filters for an aquarium that makes the aquarium clean.

So in this article, We will be providing the best canister for a 20-gallon aquarium. With reviews, comparisons, and Pros and cons of the filters.

This one was the best filter from the top 5.

Fluval 107 Canister Filter


  • Aquarium Capacity: 10 to 30 Gallon
  • Basket Volume: 1.2 L
  • Chamber Volume: 2.0L

Without wasting time, Let’s go.

Here is the list of 7 top canister filters for 20-gallon tank

Name of FiltersRatingsPrice
Fluval 107 Canister6500 + Rating with 5 StarClick Here To Know Price
Penn Plax Cascade9000 + Rating with 5 StarClick Here To Know Price
Marineland Magniflow 1603600 + Rating with 4 starClick Here To Know Price
Aqueon QuietFlow Canister204 rating with 4.5 starClick Here To Know Price
Finnex PX-150 Compact23 rating with 3.5 starClick Here To Know Price

Why Filter is Important for Aquariums?

Canister Filters

Many beginners don’t know the importance of aquarium filters. Filters are important for aquariums because they will clean the debris and remove toxic ammonia build-ups from the aquarium.

Without an aquarium filter, it was very hard to breathe for fishes. Not only that, Toxic ammonia and nitrite will affect the fish’s health.

So you need a good filter for removing the toxic ammonia and cleaning the debris from aquariums.

What happens to aquariums when ammonia starts to spread?

If the aquariums have a lot of ammonia, then it will affect the health fishes.

The ammonia will affect the fish’s gills and tissues. So the fish may have stress and leading to the death of the fish.

In order to prevent them, you can use a filter in the aquarium and provide good maintenance for cleaning the tank every month.

Does a 20-gallon tank need a filter?

The filter is important for every fish tank. To make the aquarium clean and well-maintained, you need a filter.

Every aquarium requires a filter for cleaning and removing toxic ammonia and nitrite. Without the filter, it was very hard to survive for fish because the ammonia will start to affect them.

So you need to know the importance of a filter in every aquarium.

Here is the detailed review of the Fluval FX4 canister.

What size filter should you have for a 20-gallon tank?

Canister Filters

Filter size varies according to the size of the aquarium.

So I would recommend using a filter that has at least 80 GPH. You may be worried about the GPH Values. 

Don’t worry, GPH means Gallon Per Hour. To know more about the GPH, You can visit on Detailed Blog Post Here.

The filter needs to convert 80 gallons of water per hour to maintain the quality of water and to reduce the spreading of ammonia and toxic nitrites.

How do I choose the right fish tank filter?

Canister Filters

Selecting a filter that fits aquariums is very simple and many beginners don’t know to pick the right one for them.

Sometimes, they may choose different size filters for aquariums, and due to the high flow rate, the fish may get stressed.

You need to select a suitable filter for the fish tank. I will help you for choosing the right one that fits your aquarium.

You need to measure the flow rate using the GPH (Gallon Per Hour). GPH means the amount of water that flows after filtration and it was measured in GPH. I recommend using 5 to 6 times the tank volume.

Best Canister Filter For 20-Gallon Aquariums

Now you know the importance of the filter in an aquarium. But worry about buying a canister filter that fits your 20-gallon aquarium.

Here are the 7 best canister filters for 20-gallon aquariums that I have Reviewed.

You can buy these filters from amazon through the links.

Fluval 107 Canister

Canister Filters

The Fluval 107 Canister filter was the best one on our list after reviewing and testing it. It was suitable for your 20-gallon aquarium.

It was suitable for freshwater and saltwater tank and easy to install and assemble.

The quiet working environment will make us so calm and not worried about horrible sounds that come from other filters.

Fluval 107 canister filter can be used between 10 to 30-gallon aquariums with a GPH of 145. The filter media used in Fluval 107 are bio foam, bio foam max, and sponge.

Pros and Cons

Now let’s know about the pros and cons of Fluval 107.

Pros of the Fluval 107

  • Easy To Setup
  • Easy to Maintain
  • Versatile
  • Incredible Noise Compression
  • Light Weight

Cons of the Fluval 107

  • The connection wire needs to be longer


According to my Review after testing the Fluval 107, It was one of the best canister filters for 20-gallon aquariums. You can easily assemble the filter using the instruction given inside. 

The immersive performance of the Fluval 107 will clean the water faster. So you can use this filter for 20-gallon aquariums from my recommendation.

I bought this filter from Amazon and the rating was 6000+ with 5 stars. If this filter is suitable for you, then click here to buy now.

Penn Plax Cascade 500 Canister Filter

Canister Filters

Penn Plax Cascade 500 was the second one on our list. It can be used for 20 to 30-gallon aquariums without any problems.

I think the canister filter body was transparent and you can easily see the dirty things coming from the aquarium.  The two filtration stages give us crystal-clean water without changing the water parameters.

You can easily rotate the flow valve at 360°, so it will be easy to assemble and install hoses. The filtration media is mechanical filter media and activated carbon.

Pros and Cons

Pros of Penn Plax

  • Easy to install
  • Rotate the Valve
  • Optimum Performance

Cons of Penn Plax

  • No-bio media
  • Some noise coming while working


According to my review after testing the filter, It was a good one for 20 galleon aquariums, But while working you can hear some noise from the filter.

It was difficult to clean the filter media and the replacement of activated carbons is not cheap. If you need to purchase the Penn Plax filter, then click on the link.

In amazon, the rating was around 9000+ when I purchased it and now it was currently working on the platyfish tank.

Marineland Magniflow 160 Canister Filter

Canister Filters

Marineland Magniflow 160 was another best canister filter for 20 gallons aquariums. The 3-stage filter gives crystal clear water without changing the water parameters.

It was suitable for 20 to 40- gallon aquariums and the flow rate was 160 Gph. One of the main disadvantages of the filter was a heavyweight.

If the canister has water-filled then it will be much heavy. So you need to drain the filtered water first and clean the filter media.

When it was filled with water, I got help from my brother to clean it. So try to remove the water from the filter first and carry it out for cleaning.

Pros and Cons

Pros of Marineland Magniflow

  • Easy to install
  • Good Build quality
  • Three Filteration stages
  • Smooth cleaning process

Cons of Marineland Magniflow

  • Heavyweight


According to my review after testing it, it was the best filter for a 20-gallon tank with 3-stage filtration. The maintenance of the filter was a little difficult due to the heavy weight.

The build quality and filtration process are immersive with the quiet working environment. I would suggest buying this one if you need 3-stage filtration.

In amazon, the rating of Marineland magniflow 160 is 3500+ with 5 stars. So you can buy now through the link below.

Aqueon QuietFlow Canister Filter up to 55 Gallons

Canister Filters

Aqueon Quietflow canister filter is the best to filter for 20 to 50-gallon aquariums. You can choose a different size that is suitable for your aquariums.

I just bought this filter for setting in the angle fish tank and it was working without any problems. Aqueon does its filtering job very clearly and provides us with crystal-clear water after filtration.

The filter doesn’t have heavy motors, so you can use it in your 20-gallon aquariums. The installation of the filter was a little difficult when compared with other canister filters.

Pros and Cons

Pros of Aqueon Quietflow

  • Good Performance
  • Incredibly quiet

Cons of Aqueon Quietflow

  • Time-consuming Filteration process
  • Difficult clean hose lines


According to my review, The Aqueon quiet flow was the best choice for 20-gallon aquariums. It gives crystal clear water after filtration, so you buy the filter without any objections.

One of the main problems is the time-consuming filtration process. Amazon has a 200 rating with good reviews.

In order to buy the Aqueon Quietflow 55, you can click here.

Finnex PX-150 Compact Aquarium Canister Aquarium Filter

Canister Filters

Finnex Px 150 canister was the last one on our list. This filter can be hung on aquariums and the three stages of filtration were incredible.

The filtration media includes activated carbons, ceramic rings, and a sponge. This filter was used by my friend Adin and he said me the reviews.

Pros and Cons


  • 3 Stage Filtration
  • Easy to Install
  • Low noise working


  • Hang on aquarium
  • Maintenance was difficult
  • Need to Replace the Carbon filter


I am not going to say the reviews of this filter because it was not used by me. I don’t test yet. But my friend told me this filter was good for 20-gallon aquariums.

You can buy this filter on amazon through the link.

Wrapping up

In this blog post, You have got an idea about filtration and the importance of filters in aquariums.

If these reviews help you Share this post with friends and family who loves fishes.

Leave a Reply

Your email address will not be published. Required fields are marked *