To clean a water softener, begin by dumping all water and salt out of the tank and disposing of it. Then remove the brine grid from the base of the tank and set it aside. Next, use warm, soapy water and a long-handled brush to scrub the tank’s interior, and then rinse with plain water. Once rinsed, use a mixture of ¼ cup household bleach and 2 to 3 gallons of water to fill the tank. This mixture should sit for at least 15 minutes to kill any microorganisms. Rinse the reservoir once more, then replace the brine grid, refill with water, and replenish it with salt. Keep your water softener maintained to improve the water quality in the home and prevent any drops in water pressure due to mineral buildup.