Tetra Whisper Aquarium Filter, 20-gal

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$23.17 (-20%) Chewy Price
$28.99 List Price
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Pay in 4 interest-free payments on purchases of $30-$1,500. .

About This Item

Details

  • Sound shield with Stay Clean technology produces ultra-quiet filtration.
  • Motor is submerged and does not require priming.
  • Comes in five different sizes, from 10-gallon to 60-gallon.
  • Helps keep fish healthier by maintaining an ideal pH level.
  • Uses Tetra Whisper Bio-Bag Filter Cartridges (sold separately).
Learn More About Tetra From Our Team of Experts

Frequently bought together

Questions & Answers

6 Customer Questions

does it take a large filter

Answer by Chewy • Mar 10, 2023
The 10-gallon uses a medium Tetra Whisper Bio-Bag Filter Cartridge and the 20, 30, 45, and 60-gallon all use a large Tetra Whisper Bio-Bag Filter Cartridge.

Do you get a one filter in this box

Answer by Chewy • May 05, 2022
This product includes 1 Whisper Aquarium Filter.

When should I change filter cartridges?

Answer by Chewy • May 11, 2024
The cartridges should be changed once a month.

How does this mount to the tank?

Answer by Chewy • Jan 16, 2023
This filter is designed to hang over the aquarium frame.
Reviews
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4.3
Rated 4.3 out of 5 stars
271 Ratings
Terms & Conditions

91 Customer Reviews

Rated 5 out of 5 stars
By Scherry on Oct 23, 2025

This is a great little pump!

This is a great little pump. So great in fact that I would suggest it to anyone and in fact I am getting another for my daughter. It fits my ten gallon tank beautifully

This is a great little pump. So great in fact that I would suggest it to anyone and in fact I am getting another for my daughter. It fits my ten gallon tank beautifully and keeps the tank crystal clear. And as an extra plus the top is closed so that my naughty kittys can't drink the water! 5 Stars!

Rated 1 out of 5 stars
By Dawn on Oct 14, 2025

Neon green

I redid my guppies fish tank, ordered this filter and it's awful. It made my tank NEON GREEN. Never have I had a green tank. I don't recommend this at all!!

I redid my guppies fish tank, ordered this filter and it's awful. It made my tank NEON GREEN. Never have I had a green tank. I don't recommend this at all!!

Rated 3 out of 5 stars
By Olivia on Jun 22, 2025

Great but...

Ive had this filter for about a month in my tank, I just came back from a 4 day vacation, and I noticed the power went out and the filter wasn't running. I figured

Ive had this filter for about a month in my tank, I just came back from a 4 day vacation, and I noticed the power went out and the filter wasn't running. I figured it was fine and filled the tank with more water. Still it didn't start. So I went to touch it and the electronic part of the filter was very hot. I attempted to cool it down and see if it would work, but it seems dead. Just something to he prepared for I suppose.

Rated 5 out of 5 stars
By David on Nov 4, 2025

Works good

Hasn't stopped working like my other one did. Great product!

Hasn't stopped working like my other one did. Great product!

Rated 5 out of 5 stars
By Alice on Jul 29, 2025
Top 500 Contributor

Great Price easy to use

This is the Best of Fish Filters come in 3 sizes for tanks, easy to clean good water flow and this is my second one for my 30 gallon tank. Well pleased.

This is the Best of Fish Filters come in 3 sizes for tanks, easy to clean good water flow and this is my second one for my 30 gallon tank. Well pleased.

Rated 1 out of 5 stars
By CARTER on Aug 3, 2025

It is damaged

I received the filter and opened it up and the thing that gets the suction is not connected. I want a refund please and thank you

I received the filter and opened it up and the thing that gets the suction is not connected. I want a refund please and thank you

Rated 1 out of 5 stars
By Lisa on Jul 31, 2025

DO NOT BUY

This should be removed from the store. They last 2-3 months tops. I have replaced several times. ZERO STARS

This should be removed from the store. They last 2-3 months tops. I have replaced several times. ZERO STARS

Rated 5 out of 5 stars
By Colleen on Dec 15, 2025

Working great for my smaller aquarium!

So far keeping it clean

So far keeping it clean

Rated 1 out of 5 stars
By Crystal on Aug 19, 2025

Broken

It broke I only used it for about 2 1/2 months normal

It broke I only used it for about 2 1/2 months normal

Rated 5 out of 5 stars
By Donna on Apr 3, 2025
Top 1000 Contibutor

Sooo quiet

This is so far, the quietest filter I’ve ever had. My axolotl tank is in my bedroom and I’m a light sleeper. As long as the tank water level is high, I cannot even

This is so far, the quietest filter I’ve ever had. My axolotl tank is in my bedroom and I’m a light sleeper. As long as the tank water level is high, I cannot even hear it. Love it. Shoulda got this one first.