The AquaFX Carbon Block Filter 10x2, available in a convenient case of 25, is an essential second stage component for your reverse osmosis or RO/DI water purification system. Designed specifically for saltwater aquarium use, this filter effectively removes a wide array of harmful contaminants from tap water, including chlorine, fluoride, pesticides, herbicides, and other volatile organic compounds. It also significantly improves water quality by eliminating unpleasant tastes and odors, providing a foundation of pure water crucial for a healthy reef environment. Each 10x2 inch filter utilizes high-purity coconut shell activated carbon block, capable of removing 99% of chlorine, taste, and odor. The filter incorporates food-grade, non-shedding polypropylene fabric to meticulously capture carbon fines, impurities, and sludge, ensuring consistently cleaner water for your aquarium. These filters are made from food-grade materials, are BPA-free, environmentally friendly, and feature a robust silicone O-ring to prevent any water bypass. Each individual filter can effectively process up to 3750 gallons of water at 2ppm chlorine, or an impressive 7500 gallons at 1ppm chlorine, operating efficiently up to 140F (60C) and 120PSI. This bulk case of AquaFX Carbon Block Filters is an ideal solution for dedicated reef aquarists, professional maintenance services, or anyone utilizing compatible RO systems such as the AquaFX Barracuda, Dolphin, Moray, Mako, Octopus, Hammerhead, Great White, Whale Shark, or most standard residential 10-inch canister systems. Replacing these filters every 4-6 months is critical to maintain optimal performance and to continuously supply the pristine water quality necessary for the vitality and well-being of sensitive corals, fish, and invertebrates in your saltwater aquarium.