Test the water pH with a reliable test strip or liquid test kit
Add a pH increaser product according to the manufacturer’s directions
Use soda ash to raise pH quickly if needed
Use baking soda to raise alkalinity, which can also help stabilize pH
Run the jets or circulation system to mix the chemicals thoroughly
Retest the water after 15 to 30 minutes
Repeat small adjustments until the pH reaches the recommended range
Keep the pH between 7.2 and 7.8
Check total alkalinity before adjusting pH
Avoid adding too much chemical at once
Keep the hot tub cover open briefly after adjustment to help gases escape