--- product_id: 2221488 title: "Fluval U4 Poly Cartridge, Replacement Underwater Aquarium Filter Media, 2-Pack, A492" brand: "fluval" price: "$32.76" currency: USD in_stock: true reviews_count: 13 category: "Fluval" url: https://www.desertcart.ec/products/2221488-fluval-u4-poly-cartridge-replacement-underwater-aquarium-filter-media-2 store_origin: EC region: Ecuador --- # Compatible with fresh & saltwater Dual-sided chemical filtration Polyester pad traps fine debris Fluval U4 Poly Cartridge, Replacement Underwater Aquarium Filter Media, 2-Pack, A492 **Brand:** fluval **Price:** $32.76 **Availability:** βœ… In Stock ## Summary > 🐠 Keep your aquatic world flawless β€” because your fish deserve the best! ## Quick Answers - **What is this?** Fluval U4 Poly Cartridge, Replacement Underwater Aquarium Filter Media, 2-Pack, A492 by fluval - **How much does it cost?** $32.76 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.ec](https://www.desertcart.ec/products/2221488-fluval-u4-poly-cartridge-replacement-underwater-aquarium-filter-media-2) ## Best For - fluval enthusiasts ## Why This Product - Trusted fluval brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - β€’ **Odor & Color Control:** Effectively eliminates harmful liquid substances, colorants, and odors for crystal-clear water. - β€’ **Effortless Maintenance:** Easy-to-replace 2-pack cartridges keep your tank pristine with minimal hassle. - β€’ **Trusted Legacy Innovation:** From Fluval, pioneers of 3-stage filtration technology since 1975, ensuring top-tier quality. - β€’ **Dual-Action Filtration Power:** Two unique filter sides combine for unmatched chemical and particulate removal. - β€’ **Versatile Aquarium Compatibility:** Perfectly engineered for freshwater, saltwater, and reptile tanks alike. ## Overview The Fluval U4 Poly Cartridge 2-Pack offers advanced dual-sided chemical filtration with a polyester pad that traps fine debris and a side that removes harmful liquids, colorants, and odors. Designed for freshwater, saltwater, and reptile aquariums, these cartridges ensure superior water clarity and health. Backed by Fluval’s decades-long innovation legacy, they provide easy maintenance and reliable performance to keep your aquatic environment thriving. ## Description Fluval U4 Poly Cartridges has two unique filtering sides that combine to provide thorough chemical filtration, the crucial second stage in the filtration process. The polyester filter pad side filters out fine debris and contaminants. The side filters out harmful liquid substances, colorants and odors. The Fluval Poly Cartridge helps keep your aquarium healthy and clean. For more fish tank accessories, check out other Fluval products including aquarium filters, aquarium heaters, aquarium air pumps, aquarium lights, aquarium rocks, aquarium thermometers, and aquarium stands. Fluval has a wide variety of products that are perfect for your pet fish to enjoy in any large fish tank, small fish tank, saltwater tank or freshwater tank. Fluval broke onto the aquatic scene in 1975 by introducing the world’s first 3-stage filter with synchronous motor technology – a breakthrough that is still applied in the industry today. Since then, Fluval has built a legacy around this pioneering spirit, relentlessly adapting in a changing world to launch innovative aquarium products that remain at the forefront of technology, and which set the bar in quality, style and functionality. Fluval’s mission is not just about building products that mimic the natural world, but inspiring aquarists of all skill levels to enjoy and respect the hobby for generations to come. Review: Great filter - Absolutely love the fluval filter! It's incredibly efficient at keeping my tank clean and maintaining optimal water quality for my axolotls. Setup was super easy and fast, which is a huge plus. Definitely recommend it to anyone looking for a reliable and effective filtration system for their aquarium. Review: NIce filter and lacks the visual eyesore most filters create outside the tank. - This filter is quiet and the 3 current settings are great to provide oxygen and a little action for the fish inside to all areas of the tank. I have four 4-6 inch oscars and two plecostomus in a 55 gallon tank and they have been much livelier since we got this filter. I have no room in the back of my aquarium, its almost flush with the wall, for traditional filters and my two hoods have premade cuts for openings but since I have this filter there is no need to use them. I just used some plants to cover the filter from view inside the tank and all in all, my aquarium looks great and my fish love it. I definitely recommend buying this product if you don't want or cant have a traditional filter on the lip of the aquarium tank. ## Features - Filter media with two unique filtering sides that combine to provide thorough chemical filtration - Polyester side filters out fine debris and contaminants - Side filters out harmful liquid substances, colorants and odors - Suitable for freshwater, saltwater or reptile environments - Includes two cartridges designed for use with the Fluvial U4 Underwater Filter ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B001XRVX8C | | Allergen Information | Nut Free | | Best Sellers Rank | #29,968 in Pet Supplies ( See Top 100 in Pet Supplies ) #302 in Aquarium Filter Accessories | | Brand | Fluval | | Brand Name | Fluval | | Customer Reviews | 4.7 out of 5 stars 1,948 Reviews | | Global Trade Identification Number | 00015561104920 | | Included Components | Fluval U4 Poly-Carb Cartridge, Replacement Underwater Aquarium Filter Media, 2-Pack, A492 | | Item Form | Cartridge | | Item Type Name | Fluval U4 Poly-Carb Cartridge, Replacement Underwater Aquarium Filter Media, 2-Pack, A492 | | Item Weight | 0.03 kg | | Manufacturer | Rolf C. Hagen (USA) Corp. | | Manufacturer Part Number | A492 | | Model Number | A492 | | Number of Packs | 2 | | Pet Type | Fish, Reptile | | Target Species | Fish | | UPC | 015561104920 | | Unit Count | 1 Count | | Warranty Description | Warranty | ## Product Details - **Brand:** Fluval - **Item Form:** Cartridge - **Item Weight:** 0.05 Kilograms - **Manufacturer:** Rolf C. Hagen (USA) Corp. - **UPC:** 015561104920 ## Images ![Fluval U4 Poly Cartridge, Replacement Underwater Aquarium Filter Media, 2-Pack, A492 - Image 1](https://m.media-amazon.com/images/I/519t8soBffL.jpg) ![Fluval U4 Poly Cartridge, Replacement Underwater Aquarium Filter Media, 2-Pack, A492 - Image 2](https://m.media-amazon.com/images/I/419vlD1TFCL.jpg) ![Fluval U4 Poly Cartridge, Replacement Underwater Aquarium Filter Media, 2-Pack, A492 - Image 3](https://m.media-amazon.com/images/I/21sE-eXf5PL.jpg) ## Customer Reviews ### ⭐⭐⭐⭐⭐ Great filter *by J***K on March 14, 2024* Absolutely love the fluval filter! It's incredibly efficient at keeping my tank clean and maintaining optimal water quality for my axolotls. Setup was super easy and fast, which is a huge plus. Definitely recommend it to anyone looking for a reliable and effective filtration system for their aquarium. ### ⭐⭐⭐⭐⭐ NIce filter and lacks the visual eyesore most filters create outside the tank. *by G***7 on August 14, 2013* This filter is quiet and the 3 current settings are great to provide oxygen and a little action for the fish inside to all areas of the tank. I have four 4-6 inch oscars and two plecostomus in a 55 gallon tank and they have been much livelier since we got this filter. I have no room in the back of my aquarium, its almost flush with the wall, for traditional filters and my two hoods have premade cuts for openings but since I have this filter there is no need to use them. I just used some plants to cover the filter from view inside the tank and all in all, my aquarium looks great and my fish love it. I definitely recommend buying this product if you don't want or cant have a traditional filter on the lip of the aquarium tank. ### ⭐⭐⭐⭐⭐ Works great! *by L***S on April 25, 2025* Works great! ## Frequently Bought Together - Fluval U4 Filter Carbon Cartridge - Fluval U4 Internal Filter Foam Pad - Fluval U Internal Filters Clean and Clear Cartridge, White --- ## Why Shop on Desertcart? - πŸ›’ **Trusted by 1.3+ Million Shoppers** β€” Serving international shoppers since 2016 - 🌍 **Shop Globally** β€” Access 737+ million products across 21 categories - πŸ’° **No Hidden Fees** β€” All customs, duties, and taxes included in the price - πŸ”„ **15-Day Free Returns** β€” Hassle-free returns (30 days for PRO members) - πŸ”’ **Secure Payments** β€” Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** β€” Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.ec/products/2221488-fluval-u4-poly-cartridge-replacement-underwater-aquarium-filter-media-2](https://www.desertcart.ec/products/2221488-fluval-u4-poly-cartridge-replacement-underwater-aquarium-filter-media-2) --- *Product available on Desertcart Ecuador* *Store origin: EC* *Last updated: 2026-08-08*