D.E. is historically the media of choice for the designers of some of the largest and most beautiful pools in the world. It is now more practical for all backyard pools as well. System:3 brings you the proven performance of Sta-Rite's diatomaceous earth media in the world's safest and easiest-to-operate filter. The greater cycle times and minimized maintenance of the System:3, coupled with Sta-Rite's superior grid system, gives you the finest D.E. filter available.