For example, pool filter sand can commonly filter debris as small as 20 microns, with 1 micron equal to 1/26,000 of an inch. The best pool filter sand may be able to filter particles as small as 3 ...

Fits Nautilus and Nautilus Plus pool/spa D.E. filter models NS24, NS36, NS48, NS60, NS72, NSP-24, NSP-36, NSP-48, NSP-60, NSP-72 Air Relief Valve:For Tagelus Deluxe, Sand Dollar, Sta-rite Cristal ...