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Tetra Whisper Internal Filter for Aquariums 20 to 40 Gallons, with Air Pump

Tetra Whisper Internal Filter for Aquariums 20 to 40 Gallons, with Air Pump Tetra Whisper Internal Filter for Aquariums 20 to 40 Gallons with Air Pump Tetra Whisper Internal Filter 5 to 10 Gallon with Air Pump for Aquariums

Size Descriptor:Extra Large

Key item features

UNIVERSAL DESIGN: Tetra Whisper 20-40 Internal Filter is an all-in-one air pump and water filter system.
INTERNAL FILTER: Mounts on the inside of your aquarium with clip (included).
CATCHES DEBRIS: Dense, dual-sided mesh filters debris and fish waste.
AERATES WATER: Air-driven design filters water while oxygenating water.
CONVENIENT DESIGN: Uses easy to change Bio-Bag cartridges; filter mounts inside aquarium, making it possible to place tank flush against the wall.
USE IN: Aquariums 20-40 gallons in size.

Specs

Number of stages
3-Stage
Product line
Tetra Whisper
Weight
1.55 lb
Assembled product height
5.1 in

Reviews summary

Pros

: Suitable for compact turtle habitats.
: Made to last and performs well.
: Offers good functionality at this price point.
: Produces minimal noise during use.
: Ideal for small aquariums up to 10 gallons.

Neutral

: Can be secure, but also limited by size and shape.

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Current price is $34.97

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Arrives by Fri, Jun 5

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Sold by Zen Commerce

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4.428571428571429 stars out of 5, based on 63 seller reviews(4.4)

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About this item

Product details

The Tetra Whisper 20-40 Internal Filter for aquariums is the ultimate in quiet, convenient 3-stage filtration. This submersible filter mounts on the inside of the aquarium, rather than hanging from the outside, making it possible to place the tank flush against a wall and easily hide with tank decor. The air pump (included) provides bubbles that move water through the filter, efficiently filtering and oxygenating your aquarium. The water flows through Ultra-Activated carbon, absorbing odors and discoloration, as well as through the dual-sided mesh of the Bio-Bag Filter, trapping debris and fish waste. The Tetra Whisper 20-40 Internal Filter adjusts easily to high or low water levels with a mounting clip. Each unit includes the filter, air pump, 2 feet of airline tubing and one Tetra Whisper Bio-Bag Filter cartridge.

UNIVERSAL DESIGN: Tetra Whisper 20-40 Internal Filter is an all-in-one air pump and water filter system.
INTERNAL FILTER: Mounts on the inside of your aquarium with clip (included).
CATCHES DEBRIS: Dense, dual-sided mesh filters debris and fish waste.
AERATES WATER: Air-driven design filters water while oxygenating water.
CONVENIENT DESIGN: Uses easy to change Bio-Bag cartridges; filter mounts inside aquarium, making it possible to place tank flush against the wall.
USE IN: Aquariums 20-40 gallons in size.

info:

We aim to show you accurate product information. Manufacturers, suppliers and others provide what you see here, and we have not verified it.

Specifications

Number of stages

3-Stage

Accessories

1 - Whisper filter, 1 - Air pump, 2 feet of airline tubing, 1 Tetra Whisper Bio-Bag Filter cartridge

Product line

Tetra Whisper

Weight

1.55 lb

Directions

Instructions

Mounts on the inside of your aquarium with clip (included)

Warranty

Warranty information

All products come with a 90 Day, or longer, manufacturer warranty

Please be aware that the warranty terms on items offered for sale by third party Marketplace sellers may differ from those displayed in this section (if any). To confirm warranty terms on an item offered for sale by a third party Marketplace seller, please use the 'Contact seller' feature on the third party Marketplace seller's information page and request the item's warranty terms prior to purchase.

Warnings

WARNING: WARNING: This product can expose you to some chemicals, which is known to the State of California to cause For more information, go to www.P65Warnings.ca.gov.

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tetra whisper internal filter

turtle filter

tetra filter

aquarium filter pump

20 gallon filter refill

Customer ratings & reviews

4.3 out of 5 stars

stars1,082 ratings349 reviews

How item rating is calculated

Reviews summary

Pros

: Suitable for compact turtle habitats.
: Made to last and performs well.
: Offers good functionality at this price point.
: Produces minimal noise during use.
: Ideal for small aquariums up to 10 gallons.

Neutral

: Can be secure, but also limited by size and shape.

Generated by AI

Customer photos

+33 images

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Showing 1-3 of 349 reviews

Jun 8, 2025

WalmartCustomer

Item details

Size descriptor: Large

5 out of 5 stars review

Verified Purchase

The pump was easy to install, it works just like it should, and it was delivered rapidly. The price was not out of line compared to other options, but everything is overpriced these days.

Incentivized Review

Helpful?

Feb 25, 2026

Jessie

Item details

Size descriptor: Large

5 out of 5 stars review

Verified Purchase

works very well!

I ordered this filter for a 10 gallon tank. I do not have fish in it yet, but I do have a few live plants. My tank also has sand substrate with waterlogged wood pieces. My old filter crapped out on me finally so I decided on this one to replace it as it was a fair price. I was AMAZED at how quickly it cleared up my tank. it had a thick layer of sediment on the bottom and this filter cleaned it right up, I was shocked! It's also whisper quiet, I can't even tell if it's on, sometimes I have to double check to make sure it's still running. lol Highly recommended!

Helpful?

Apr 30, 2026

Sally

Top Reviewer

Item details

Size descriptor: Extra Large

5 out of 5 stars review

Verified Purchase