What Is The Best Canister Filter For A 20 Gallon Fish Tank?

Our Top Canister Filter For A 20 Gallon Tank

Fluval 107 Perfomance Canister Filter

Buy The Fluval 107

Finding Canister Filter For A 20 Gallon Tank

If you’re looking for help with picking a canister filter for a 20-gallon tank then keep reading….

The following is a question from one of our TFCG community members.

Question: “Hello, I’m looking for a canister filter for a small aquarium, but I’m worried that a canister filter will be too strong.

What size canister filter do I need for a 20 gallon tank?”

In this post, you will learn how to select a canister filter that will be perfect for your 20-gallon tank and not break the bank doing it.

Here are the top four average-priced canister filters for a 20-gallon tank:

If you’re thinking of using a canister filter in your 20-gallon tank you may have thought…

Further Reading: Need Help Finding A Canister Filter? Our Guide Can Help You Find The Best Canister Filter For Your Aquarium And Your Needs. We’ve Reviewed All The Top Brands From Fluval, Ehiem, API, Marineland, And More.

Is A Canister Filter Too Strong For A 20-Gallon Tank?

If that’s you, don’t be concerned.

A canister filter can help keep your 20-gallon tank clear and clean and in my opinion, is the better option over any other filter set up.

In general, the main difference between canister filters and power filters is the amount of water that can be processed per hour.

As an example;

The Marineland Penguin Power Filter can filter 150 GPH, whereas the Marineland Magniflow 160 Canister Filter will run 160 GPH.

Both are good but as you can see the Marineland Magniflow can process more than the Marineland Penguin Power Filter.

But the flow rate is not really what makes a filter efficient!

What really sets apart canister filters from power (HOB) filters is the media area available for beneficial bacteria to grow on.

“Canister filters have a far superior advantage when it comes to media capacity when compared to other filters.”

Canister filters have huge trays which allow you the ability to provide all the filter media options you can think of.


How to Pick a Fish Tank Filter

Okay, Okay, But Can You Over Filter A Fish Tank?

In my experience, no.

More filtration is better.

I personally have a 20-gallon aquarium with a canister filter rated for a 75-gallon tank and it keeps the tank crystal clear.

So How Do You Determine The Right Size Canister Filter For Your Tank?

In general, the rule of thumb is that your filter should pass all the water in your tank through the filter at least four times per hour.

As an example:

If you have a 20-gallon tank, you should have a canister filter with a flow rate of at least 80 gallons per hour.

If the filter choices are between 80-100 gallons per hour, you should always move to the higher flow rate.

Most aquarium canister filters will show you on the box the intended tank size along with the flow rate usually in gallons per hour.

Here are four canister filters that follow our rule of four and have a flow rate of at least 80 gallons per hour which would be well suited for a 20-gallon tank:

Penn Plax Cascade 500 Canister Aquarium Filter 

Penn Plax Cascade 500 GPH Canister Filter

Get The Penn Plax Cascade 500 Canister Filter

Rated for a 30-gallon tank with a flow rate of 115 gallons per hour.

Fluval 106 External Canister FilterFluval 107 Perfomance Canister Filter

Buy Fluval 107

Rated for a 25 gallon tank with a flow rate of 145 gallons per hour.

Marineland Magniflow 160 Canister Filter 

MarineLand Magniflow Canister Filter for Aquariums

Get The MarineLand Magniflow Canister Filter

Rated for a 30 gallon tank with a flow rate of 160 gallons per hour.

Eheim Classic Canister Filter with Media – 2213EHEIM Classic Canister Filter 2211, Classic 150 - PetOverstock

Get The EHEIM Classic Canister Filter

Rated for a 65 gallon tank with a flow rate of 116 gallons per hour.

Note: You may have noticed the Eheim Canister Filter (Above) says it’s rated for a 65 gallon tank with a flow rate of only 116 gallons per hour.

This doesn’t follow my rule of thumb to pass the volume of the tank through the filter four times.

However, for a 20-gallon tank, the Eheim 2213 has more than enough flow rate.

If you’re worried about the current from a canister being too strong for your 20 gallons?

Don’t be!

Most canister filters come with adjustable output flow tubes, a spray bar which can be used to slow down the current and you can use a pre-filter device on the input tube which will slow down the current even more.

So What Is The Best Canister Filter For A 20 Gallon Fish Tank?

MarineLand Magniflow Canister Filter for AquariumsOut of the four canister filters noted above, the best and most affordable canister filter for a 20-gallon tank would be the;

Marineland Magniflow 160 Canister Filter

It is an efficient and average priced between ($70-$80) canister filter well suited for a 20-gallon tank and provides you the highest flow rate at 160 gallons per hour.

Fluval 106 External Filter

If you don’t like the Marineland Magniflow another good canister filter for a 20-gallon tank worth the price is the;

Fluval 106 External Canister Filter

It costs slightly more but Fluval is one of the best filter producers and the Fluval 106 provides you with an awesome 145 gallons per hour flow rate.

And if you’re still not sure if a canister filter is right for your 20-gallon tank,

click here for more fish tank filter reviews along with the best aquarium filters for 20-gallon tank.

Further reading: Beautiful Ideas For Centerpiece Fish For A 20 Gallon Tank

Jack Dempsey
Follow Me