Each type has advantages: Sand filters are low-maintenance (just backwash) and handle large debris well. Cartridge filters catch finer particles, are easy to clean, and don't require backwashing. D.E. (diatomaceous earth) filters provide the finest filtration (down to 2–5 microns) for crystal-clear water but require more maintenance. HTH offers filter sand and D.E. filter aid to support sand and D.E. filtration systems. HTH™ Pool Care Filter Cleaner can be used on sand, D.E., and cartridge filters to remove oils, minerals, and debris, improve filtration efficiency, and help extend filter life.