The GrowMax Green Carbon Block Filter 10" is a high quality replacement carbon filter, specially developed for effective water purification. At 25cm long, this filter is designed to retain chlorine, organic pollutants, tastes and odors, making it ideal for home and garden use water treatment systems The carbon block is designed to provide maximum filtration efficiency while maintaining high water flow It is suitable for both aquariums and hydroponic and horticultural systems where water quality is critical The filter is easy to installation and replacement, ensuring your systems will always have access to clean, healthy water.