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Tetra

Tetra Whisper Internal Filter 20 To 40 Gallons, For Aquariums, In-Tank Filtration With Air Pump

  • Based on 21,204 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives Monday, May 26
Order within 7 hours and 35 minutes
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Size: Up to 40-Gallons


Features

  • UNIVERSAL DESIGN: Tetra Whisper 40i 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 up to 170 GPH while oxygenating water.
  • CONVENIENT DESIGN: Uses large easy to change Bio-Bag cartridges; filter mounts inside aquarium, making it possible to place tank flush against the wall.

Description

The Tetra® Whisper® 40i 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 décor. 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. Filters up to 170 GPH while oxygenating water. The Tetra Whisper 40i 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 medium Tetra Whisper Bio-Bag Filter cartridge (change monthly – replacement small filter cartridges available). For 20-40 gallon tanks. Since 1951, Tetra has developed the world’s most comprehensive body of fish food knowledge, and fishkeeping enthusiasts have looked to the brand for products and solutions that add ease and beauty to their home. Whether you're an experienced hobbyist or just starting out, Tetra has everything you need – from a large variety of quality fish food and innovative equipment to test kits and decor.

Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 5.85 x 5.09 x 10.29 inches; 1.5 Pounds


Item model number ‏ : ‎ AQ-65818


Department ‏ : ‎ Unisex-Adult


Batteries ‏ : ‎ Product Specific batteries required.


Date First Available ‏ : ‎ June 9, 2004


Manufacturer ‏ : ‎ Tetra


Country of Origin ‏ : ‎ China


Best Sellers Rank: #1,634 in Pet Supplies (See Top 100 in Pet Supplies) #2 in Aquarium Filters


Item Weight: 1.5 pounds


Department: Unisex-Adult


Manufacturer: Tetra


Country of Origin: China


Item model number: AQ-65818


Batteries: Product Specific batteries required.


Date First Available: June 9, 2004


Item Package Dimensions L x W x H: 10.45 x 6.02 x 5.1 inches


Item Dimensions LxWxH: 5.85 x 5.09 x 10.29 inches


Item Weight: 1.5 Pounds


Brand Name: Tetra


Target Audience Keyword: fish


Directions: See label for details


Warranty Description: See label


Model Name: Whisper Internal Filter


Color: Black


Size: Up to 40-Gallons


Material: 100% Polyester


Age Range Description: all ranges


Number of Items: 1


Included Components: Whisper In-Tank Filter 40i (upto 40 Gal)


Specific Uses for Product: Indoor


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, May 26

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • Love, Love This Filter!
Size: 5 - 10 Gallons
Okay so... I have a 20 gallon temporarily for my 4 inch turtle. I accidentally bought the smallest of this tetra filter, so I bought the medium sized one in it's place. I had only had the tank filled halfway anyway since my turtle was only 1.5 inches at this point. Mind you I didn't realize how fast they grow, and had no idea that Its recommended to have a filter that can filter 2 to 3x the tank size. So I decided to keep both filters in my tank. One on each side. Even though I still don't reach the recommended filter size, my water now almost filled to the top, stays absolutely clean. Turtles are pretty messy so I still have to do the weekly cleanings and all that extra stuff that apparently those who spend hundreds of dollars on filters still have to do as well. I don't know if this is some kind of luck thing, I don't know if maybe my turtle just isn't that dirty (yea right, I see him)... but I'm actually not looking forward to switching out my filter for the 'recommended' filter size, as these filters work so good. I love them. They are both very quiet. Aside from the sound of the water falling back in.. I mean it sounds like a waterfall. Who doesn't want to hear a waterfall? I love it. This can also be prevented by raising the water level or lowering the filter itself. Basically the closer it is to the water, the quieter it is. Such a simple device, yet so beautifully sufficient. The little one stopped working at one point and I thought... welp there you go! Get what you pay for. But nope! Removed the base, pulled out the magnetic spring propeller and tube, cleaned it out and like magic it started right up as soon as I plugged it back in. Love how easy it is to replace the filters. The filters themselves are great and definitely hold on to some dirtiness. One thing I'll say is there is quite a bit of unused empty space. I now take advantage by adding some extra media, but I must say that these filters work great even without the extra. Love this filter and would recommend above any other filter. ... show more
Reviewed in the United States on September 29, 2023 by TruthTeller
    • Perfect replacement
Size: 1 - 4 Gallons
Great fit for our 5gallon tank. It appears to work well and is very quiet, the design is versatile to fit most tanks. It’s a good value for the money. It appears to be quality built.
Reviewed in the United States on December 27, 2024 by Brandy Hughes Dorriety
    • Works perfectly
Size: 5 - 10 Gallons
Review Image by DanB DanB
Review Image by DanB DanB
The media could not be loaded. I have to say I'm quite impressed of how good it works. It keeps my turtle's tank clean and doesn't make much noise as I was expecting so it really was kept me satisfied with the purchase. I had to unplug it at the first use because my turtle was playing with it and trying to move it (I guess because it was her first time seeing it and was curious) I didn't put enough water and when plug it back in I thought it got damaged because it wouldn't turn on but it's a little tricky because I won't start until you fill it in with the right amount of water. Pretty amazing device and just for a few bucks. 😊 My turle is happy and got used to it already after a day of installing it. She loves the bubbles and the waterfall sound effect (which is relaxing and minimal) I bought the huge filter on mistake so I had to order another one but that's ok because my turtle is growing super quick and soon I'll need to get a bigger tank. Second size filter fits perfect for now. ... show more
Reviewed in the United States on September 17, 2024 by DanB DanB
    • Works very well and worth every penny!
Size: 5 - 10 Gallons
The anchor that hangs on the back is really long so the filter itself has a large footprint in your tank, but it’s worth it. Mine tipped and dumped water out of the tank and continued running dry all night. I was SHOCKED when I refilled the tank and it still worked and started filtering immediately. The tipping was user error because making room for it has been a challenge with all of my established plants. It’s my favorite, most reliable filter I’ve ever purchased for its ease of set up, cleanliness and reliability. One less star because of the anchor and footprint but well worth the money. ... show more
Reviewed in the United States on July 2, 2024 by Amazon Customer
    • Better than expected
Size: 1 - 4 Gallons
I purchased this and I also purchased a pump separately not knowing I didn’t need to the value of the money is incredible. I can’t believe how well it works and I returned the separate pump that I bought. I have a dragon scale beta Charlie, and he is very happy now And I’m sure I will be too because I won’t have to change the water as frequently. ... show more
Reviewed in the United States on January 8, 2025 by kim penta
    • Malfunctioned within 2 weeks, too large for small tank
Size: 1 - 4 Gallons
I just bought this to replace a little filter that came with my 2.5 gal goldfish tank. It was kind of large for the tank and then you can't put a lid on the tank with this one unfortunately. It worked nice at first then went downhill fast, within 2 weeks.. About a week ago I found a small pool of water around my tank and thought it was weird but wiped it up, cleaned the tank and didn't think about it again. Three nights ago, the filter was making an awful, loud, screeching noise.. we unplugged and replugged it in and then it was OK. Last night we came home and 1/2 of my tank water had been pumped out, went behind our cabinets and the water left in the tank was dirty. I think from reading other reviews, this will pump the water out of the back bubbling over and out of the tank. We were not home when this happened so I cannot confirm but I do believe this is what happened last night. I threw it out - can't trust it and it barely lasted so it doesn't seem worth it to buy a replacement. I cannot recommend this product after that! Thankfully it couldn't reach the last 1/2 of my water or my fish would be dead! ... show more
Reviewed in the United States on December 26, 2024 by Lauren F

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