Capacity: 2,000 grains, Maximum Flow: 0.5 gpm (1.9 Lpm) Softening cartridge reduces scale forming minerals like calcium and magnesium in hard water situations. May be used on water having up to 30 grains hardness per gallon (500 mg/L) at flow rates of up to 1/2 gallons per minute. Sanitary quick change cartridge makes replacement easy. Should be with an Everpure fine filter cartridge installed in a series plumbed twin head. Features Scale Control