Eliminate hard water with this reusable cartridge and your Clear Inline Hose Filter! Insert the water softener cartridge into your Clear Inline Hose Filter Canister to eliminate hard water as it travels through the hose. Once the filter and cartridge is in place, there are no extra steps required. Just turn on the water to get softened, silky water straight from the water hose. This cartridge neutralizes calcium and magnesium in the water, thereby eliminating hard water. Your car shampoo will lather better and your vehicle will be free of those nasty water spots. This cartridge can be renewed and reused indefinitely. A water softener works by replacing the calcium and magnesium ions with sodium ions. Sodium ions are soft. They don't produce scale and they don't stain. They change the actual texture of the water, making it feel slippery. This causes water to sheet off the vehicle more effectively. Water that remains on the vehicle will not leave spots. The water softener cartridge can be recharged with the 2 lb. Filter Rejuvenating Tablets. Pour enough tablets to cover the bottom of a bucket or plastic dishpan. Cover the tablets with water and let the cartridge soak in the solution overnight. It will work like new again!