Greensand Filter Regenerant

Potassium permanganate is an oxidizing chemical that regenerates the manganese dioxide coating on greensand filter media. Greensand oxidizes dissolved iron, manganese, and hydrogen sulfide, causing them to form solid particles that the media then traps. Without periodic regeneration, the media loses its oxidizing capacity and contaminant removal drops.

Typical dosing is 1 to 4 ounces per regeneration cycle depending on media volume and contamination levels. Follow your filter system manual for the exact concentration. Use a 1 to 2 percent solution mixed in the brine tank or injected directly into the backwash cycle as specified by the system design.

It is a strong oxidizer and skin and eye irritant. Always wear gloves and eye protection when measuring and mixing. Store in a sealed container away from heat, flammable materials, and organic compounds. Rinse any contact area with water immediately. It is not safe to ingest and should be stored out of reach of children.

Signs include iron or manganese appearing in treated water, sulfur odor returning, or water discoloration. Some controllers automate regeneration on a timed schedule. Testing treated water monthly with an iron test kit gives a more accurate picture of when the media is exhausted and regeneration is due.

Residual potassium permanganate in treated water will stain fixtures and laundry pink or purple. A properly sized and operated greensand filter will consume all the permanganate during regeneration. After regeneration, a thorough backwash rinse is essential before returning the filter to service to prevent staining.