Spa size
Typical hot tubs hold 250-500 gallons. Check your owner’s manual for the exact volume. Round to the nearest 50 gallons if unsure.
Sanitizer type
Chlorine (dichlor granules) is most common – cheap and effective. Bromine is gentler on skin and works better at high temps. Salt systems generate chlorine automatically.
Current water test results
Target sanitizer levels: chlorine 1-3 ppm, bromine 3-5 ppm. Use test strips weekly or a digital tester monthly.
Chemical adjustments needed
pH adjustment—
Alkalinity adjustment—
Sanitizer dose—
Calcium hardness—
Shock treatment—
Always adjust total alkalinity first, then pH, then sanitizer. Add chemicals one at a time with the pump running and the cover off. Wait at least 20 minutes between additions. Never mix chlorine and bromine in the same water. Retest before using the tub.