This food-grade Polyphosphate crystals refill pack gradually dissolve in water and work by coating the iron, calcium and manganese found in hard water with the polyphosphate. This prevents limescale from adhering to surfaces within your water system and also inhibits corrosion.

By preventing limescale build-up in your boiler and hot water system you will cut the cost of your energy bills year on year as well as protecting your boiler, immersion heater and other equipment.