When to Use Stabilized Chlorinating Granules
If your chlorine level is below 3ppm (Use Chlorine Test Strips to check)
To maintain your hot tub’s chlorine levels between 3-5ppm
To raise your hot tub’s chlorine levels quickly
To aid in clearing cloudy water
To shock your hot tub once a week for maintenance purposes
 
When Not to Use Stabilized Chlorinating Granules
If you have used bromine tablets or granules without draining the hot tub
If your chlorine levels are over 8-10ppm