IPW Industries Inc. Replacement gravel for filter tanks. This is a 5 lb bag of garnet gravel that can be used under any filter media. Contact us directly for other types of gravel or other filter media needs. Additional Details ------------------------------ Bullet point: IDEAL SUPPORT FOR WATER FILTERS: This 5-pound box of gravel offers an exceptional support for various water filtration applications, from water softeners to water tanks and mixed media filtration systems. Designed to improve backwashing efficiency, it provides optimal under-bed layer that helps distribute water flow evenly, increasing the effectiveness of the primary water filtration media. Use it in water conditioners, carbon filter tanks, and mixed-media systems for enhanced water filtration.