A natural, non-toxic, biodegradable, perfect replacement for D.E. Adding ZeoFiber to sand and cartridge filters will give pool water a more polished look and removes oils not always filtered out by other filter media. Traps smaller particles, resulting in cleaner, clearer water. With the extended time between cycles you will have fewer backwashes, using less water chemicals, filter media and spend less time with maintenance. NSF/ANSI-50 approved for use in all D.E. filters.