Softenizer Ion-Exchange Resin Reusable refill of Ion-exchange resin for Softenizer. You can use this product repeatedly for a long period of time: for recovery, soak it into salt water. Please replace the resin once its surface becomes worn out and dried. Necessary amount: Softenizer 20 / approx 20ml Softenizer 50 / approx 50ml Softenizer 300 / approx 250ml * Approximately 40ml of Resin is necessary to lower the hardness level by 1°dH of every 100L of water. * For recovering a 100ml of resin, mix in the water with 20g of salt, and leave it for about an hour. Then replace the water and remove salt.