Replacement Media for Tier1 Precision Series 30,000 Grain High Efficiency Digital Water Softening System for Hardness, Iron and Manganese Reduction (1-3 Bathrooms)The Tier1 Premium Media blend also allows you to filter up to 4 ppm of Iron and 2 ppm of Magnesium. By reducing these chemicals not only can you see, smell, and taste the improved quality of your water but you can trust its filtering out harmful contaminants and improving every drop.