Replace resin without replacing the cartridge!
A water softener works by exchanging sodium ions with calcium and magnesium ions, the minerals primarily responsible for hard water. What makes the water softener cartridge work is the sand-like resin found inside the cartridge. A money-saving option is to replace the resin rather than replacing the cartridge. This Deionizer Resin Refill is 1.25 lb. of resin to replace the used resin inside the cartridge. Though the water softener cartridge can be recharged several times, it can eventually become too laden with sodium to be completely recharged. When your water begins to feel less "soft" it is time to change the resin.
To change the resin, unscrew the one lid on either end of the water softener cartridge. Remove the foam and empty out the old resin. Pour the entire contents of the Deionizer Resin Refill into the cartridge and replace the foam and lid. The water softener cartridge is now ready for use. The refill resin you receive may be a different color than the resin currently inside the water softener cartridge. The color has no impact on the resin's effectiveness.