 APY annual percentage yield, insured by NCUA. With a Culligan softener system, you'll enjoy spot-free dishes, brighter laundry, smoother hair and skin, and longer-lasting appliances. Culligan's high-efficiency system saves on water and energy, making it eco-friendly and the world's most efficient system. Want better drinking water? With cutting-edge filtration, reduce more than 70 contaminants from your water with a Culligan reverse osmosis system. Purchase a water softener from Culligan of Idaho Falls and Pocatello and get a Culligan drinking water system free for the first three months.