pH Increaser and pH Decreaser
pH chemicals adjust spa water acidity so sanitizer works properly and the water feels comfortable.
Need a dosing estimate? Open the free Spa Chemical Calculator.
Why this chemical is used
pH increaser raises low pH. pH decreaser lowers high pH. Both should be added carefully because spa water volume is small.
When it is needed
Low pH can be corrosive and irritating. High pH can cause scale, cloudy water, and weaker sanitizer performance.
How to use it safely
- Test before adding anything.
- Calculate dose based on actual spa volume.
- Add chemicals separately with circulation running.
- Wait, circulate, and retest before adding more.
- Follow the product label and spa manufacturer instructions.
Small spas are easy to overdose. When unsure, add less, circulate, and retest.
Next step: test your water, enter your readings into the calculator, then adjust slowly and retest.
Recommended spa supplies
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pH decreaserSpaGuard pH Decreaser
Lowers high pH carefully in small water volumes where overdosing happens fast.
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Bromine tabletsClorox Pool&Spa Spa Bromine Tablets
Useful for steady sanitizer in bromine spas when matched to the feeder and product label.
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Filter cleanerLeisure Time Filter Clean Cartridge Cleaner
Breaks down oils and residue that rinsing alone leaves inside cartridge pleats.
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