Calcium reactors have evolved into several types that require different media sizes. Because of this, we now offer ARM Coarse for rapid upflow type reactors that have become so popular. This coarse grade of ARM will prevent the clogging and upkeep associated with fine media and these reactors. ARM Coarse typically contains: 416,000 ppm  Calcium; 577,000 ppm Carbonate; 3,300 ppm Strontium; 1,400 ppm Magnesium; and 56 ppm Potassium.

Average density is 70 lbs/ft3.