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Pool Alkalinity Calculator

Calculate the exact amount of baking soda or acid to adjust your pool's total alkalinity for stable pH levels.

Alkalinity Calculator

Adjust total alkalinity to stabilize pH

Low

Ideal Range: 80 - 120 ppm

Total alkalinity acts as a buffer to prevent pH swings. Low alkalinity causes pH to fluctuate; high alkalinity makes pH hard to adjust.

Pool Volume

20,000 gallons

Need to RAISE alkalinity by 40 ppm

Amount to Add

11 lbs

Baking Soda (Sodium Bicarbonate)

179 oz
Large increase - add over multiple days, max 10 ppm per day

Tips

1.4 lbs per 10,000 gallons raises TA by 10 ppm

Raising alkalinity also slightly raises pH

pH and Alkalinity Relationship
Always adjust alkalinity BEFORE adjusting pH. Raising alkalinity also raises pH slightly. Lowering alkalinity requires acid which also lowers pH.

About Total Alkalinity

Total alkalinity (TA) is a measure of your water's ability to resist changes in pH. Think of it as a pH buffer - proper alkalinity keeps your pH stable. The ideal range is 80-120 ppm.

The pH-Alkalinity Connection

Low alkalinity: pH bounces unpredictably (pH bounce), corrosive water.
High alkalinity: pH tends to drift high, hard to adjust, cloudy water, scale formation.

Adjustment Order

Always adjust alkalinity FIRST, then pH. Raising alkalinity also raises pH slightly. When lowering alkalinity with acid, pH will drop too - you may need to raise pH afterward.