Note: The biochemical cotton will be vacuum packed and compressed when it is packaged and shipped. If you find that the biochemical cotton is small, deformed or not thick enough after receiving the goods, put the biochemical cotton flat for 1-2 days, the biochemical cotton will be Restore to the original state, vacuum compression will not have any effect on the filtration performance of the biochemical cotton, please rest assured to use it after the biochemical cotton is restored to its original state. Description The Biochemical Filter has the best effect on decomposing the excrement and the forage leftover. Its multi-porous feature will avoid blockages and provide the largest adhesion area for bacteria. The material has great thickness, it is durable Very suitable for using in freshwater and marine water. Can be cut any sizes as your needed. Lightweight softness design. Excellent water permeability. Cultivate the nitrifying bacteria for biological filtration. Dense shape makes it effective to avoid residue. Can be used again after cleaning 100% brand new unused Color: black. Advise: Replace the bio-sponge three month, to ensure the filtrating effect as well as the growth of the nitrifying bacteria. Note: There may be an error of 0~2cm in manual cutting, Those who mind should buy with caution. Package include:1x filter biochemical cotton Specifications: Material: High-Density Biochemical Cotton Functions: 1. Cultivate Nitrifying Bacteria for Biological Filtration Functions: 2. Break Down Manure and Leftover Forage Functions: 3. Excellent Water Permeability Functions: 4. Suitable for Fresh and Saltwater Environments Functions: 5. Reusable After Cleaning Size Options: Available in 15, 25, 35, and 50 PPI Features: **Optimized Aquarium Filtration** The Aquarium Accessories Biochemical Cotton Filter is a versatile and essential addition to any aquarium or pond. Designed to provide superior chemical filtration, this sponge filter is not only practical but also keeps floating debris at bay. Its high-density foam construction ensures that it can effectively break down manure and leftover forage, maintaining water quality and preventing the buildup of harmful residues. With a range of sizes available, from 15 to 50 PPI, you can select the perfect fit for your aquatic environment, whether it's a small fish tank or a large pond. **Ease of Maintenance and Reuse** The filter's durable material is not only thick but also designed to be reusable after cleaning, making it an eco-friendly choice for aquarium enthusiasts. The biochemical cotton's excellent water permeability allows for efficient filtration without compromising water flow. The filter's lightweight and soft design make it easy to handle and install, while its dense shape ensures that it can effectively avoid residue buildup. Remember to replace the bio-sponge every three months to maintain optimal filtration and bacterial growth. **Versatile and Adaptable** This biochemical cotton filter is not only suitable for freshwater and seawater environments but also can be cut to any size as needed, making it a versatile tool for aquarium maintenance. Its multi-porous feature ensures that it avoids blockages, providing the largest adhesion area for beneficial bacteria. The filter's black color is aesthetically pleasing and blends seamlessly with any aquatic setup. Whether you're a seasoned aquarist or a beginner, this filter is an essential component for maintaining a healthy and thriving aquatic ecosystem.