Color Indicating Anion & Cation Resin Refill Packs
The Cation Resin is a negatively charged resin, thereby attracting/removing positive ions such as Calcium.
The Anion Resin is a positively charged resin, removing/attracting negative ions such as silicates.
Both of these resin are color indicating; as they exhausts the change from a deep Purple/Blue to a light Amber.
This helps reduce the amount of DI used.
Normally there is some more positive or negative ions in your water, by removing them separately you will get FULL use of your resins.
By following these two resins with a mixed bed DI, you will neutralize the pH. If one of the 2 exhausts, the mixed bed DI will do the job.