ResCare RK41N All-Purpose Water Softener Cleaner Liquid Refill, 1 Gallon Res Care Liquid Resin Cleaning Solution 1 Gallon Best All Purpose Water Softener Cleaner Pour 4 ounces (1/2 cup) of Pro Res Care resin cleaner per cubic feet and manually regenerate softener to clean resin Extends the life of your water softner Use 4 oz. on a regular basis to clean softener resin