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Tetra Bio-Bag Disposable Filter Cartridges - Small by by Tetra

Best Seller
  • $3.99
  • (50%)
In Stock. Ships within 1 business day.
SKU: WL25900
UPC: 046798259008
MPN: 25900
  • $18.99
  • (38%)
In Stock. Ships within 1 business day.
SKU: WL25900M
UPC: 700256885306
MPN: 25900M

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1-888-373-8686 [email protected]

Product Description

Tetra Whisper Bio-Bag Cartridge replacements complete the Whisper Power Filter package for a clean, easy-to-maintain aquarium. Filled with ultra-activated carbon, these ready-to-use disposable filter cartridges remove waste particles, odors and discoloration for crystal clear water.

  • Genuine Whisper filter cartridge replacements
  • Keeps water crystal clear
  • Removes odors and discoloration

Bio-Bag cartridges are tough on the debris that makes aquariums nasty. Ultra-activated carbon absorbs odors and discoloration and dense, dual-sided mesh catches debris and fish waste better than other brands to keep your fish tank clean. Replace cartridges once a month for maximum filter efficiency.

Tip: Replace Bio-Bag cartridges when water begins to overflow excessively from the Wonder Tube chamber.


  • Small : Fits Whisper In-Tank Filter 3i
  • Medium: Fits Whisper Power Filters 10i, E, J, 10 and MicroFilter
  • Large (formerly Regular): Fits Whisper Power Filters 20i, 40i, C, 20, 30, 40 and 60
  • X-Large: Fits Whisper Power 4 and 5 Power Filters

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Enjoy free saver shipping on orders over $49, even the BIG stuff. Keep what you like and send back any unused items within 30 days.

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100% Satisfaction Guaranteed

We always want you to be satisfied when you shop with us. If not, contact us within 30 days for a replacement or a refund.


Lisa, Norton MA on 03-09-2015
Super deal!

Received my order promptly and cartridges were a perfect fit. Easy to install and super price! Will be ordering again in the very near future!

Emily, Long Beach CA on 01-22-2011
Easy to deal with

These are so cheap that I don't mind how often I change it. I have a 5 gal tank with a fancy gold fish, a pleco, and a tiny air pump filter that uses the smallest of the biobag filters. I've never had any problems with it other than algae building up in it from the algae chips I feed my pleco, which is easily solvable by taking the filter out, rinsing it and putting a fresh cartridge in. I wouldn't recommend it for large fish communities, even if you get the larger filters. Larger communities need more bio filtration, and mechanical filtration than the simple carbon based biobag cartridges/filters can offer.

Trish, Phoenix AZ on 09-20-2010
easy use

we are novices in the the"Aquarium hobby" and find the whisper bio bag an easy and positive producer. (The fishies like it too!) Trish

Mike, Henderson KY on 08-23-2010
Easy and works

This filter fits snugly enough to catch everything. It's beyond simple. The carbon dust rinses out quickly. Three days without the filter is dirtier than two weeks with the filter; although I try to try to change the water weekly.