****5 lbs ****Acid Neutralization Media. Calcite/Corosex Mix: Naturally-occurring mineral rock consisting of approximately 95percent calcium carbonate and 3percent magnesium carbonate. Used to raise pH of acidic water Acidic waters on contact with Calcite slowly dissolve the calcium carbonate media to raise the pH which reduces the potential leaching of copper, lead and other metals found in typical plumbing systems. Advantages: High uniformity coefficient for maximum contact for controlled pH correction Slower reacting Inexpensive Physical Properties: Color - Near White Density - 100 lbs./cu. ft. Composition - CaCO3, 95percent minimum - MgCO3, 3.0percent maximum Conditions for Operation: pH - 5 - 6 Bed Depth - 24 - 30 in. Backwash Rate - 8-12 GPM/sq. ft. Backwash Bed Expansion - 35percent of bed depth