MatrixCarbon, 4 L / 1 gal. Spherical Bead Shape For Optimum Hydrodynamics That Will Not Pack Like Competing Products Permits Maximum Water Flow And Contact With Is High Density Of Macroporous Binding Sites MatrixCarbon has a very low ash content as indicated by its minimal impact on pH; even when added to distilled water it does not raise above a ph of 7 Outperforms Other High Grade Carbons By At Least Two Fold When Compared For Total Capacity To Remove Organic Matter, Rate Of Adsorption, And Duration 250 Milliliters Treats 100 Us Gallons For Several Months