Is this a baking soda calculator?
It scales the named manufacturer's Alkalinity First table. It does not endorse substituting another package, purity or blend.
Pool Alkalinity Calculator
Estimate a quantity for the named Alkalinity First product using its manufacturer's table. This is a total-alkalinity planning tool, not a pH calculator or a treatment prescription.
Published by Pool Cost Planner. Updated October 19, 2026.
Use a measured water volume and current reading. The calculator does not choose a chemical target.
One product model, not interchangeable chemicals
The supported product is ARM & HAMMER Alkalinity First sodium bicarbonate. Confirm the package and target before using the table estimate. A product marketed as pH increaser, acid or a blended balancer cannot be substituted. Current and target readings both use total alkalinity in ppm as calcium carbonate (CaCO3), not ppm sodium bicarbonate.
Total alkalinity is different from pH
This tool does not predict a pH change. A pH reading is not a substitute for a measured total-alkalinity reading. The target belongs to your product and equipment guidance for the actual water conditions, not a universal preset. If the current reading exceeds the target, the output is zero additional product; no acid or lowering treatment is calculated.
Methodology: scale the manufacturer's product chart
The published Alkalinity First chart uses 9 lb per 10,000 US gallons for a 60 ppm increase. This calculator proportionally scales that rounded product guidance and supports increases up to 60 ppm. It does not claim an exact pure-chemical stoichiometric result or apply a second purity correction. Measurement uncertainty still matters.
| Water volume | Entered increase | Product-table estimate |
|---|---|---|
| 10,000 US gal | 60 ppm as CaCO3 | 9 lb |
| 5,000 US gal | 20 ppm as CaCO3 | 1.5 lb |
| Any supported volume | No positive increase | 0 lb |
Before acting on an estimate
Verify water volume, repeat an unexpected test result and match the product label to the model. Obtain product-specific help when the increase is outside the supported range, multiple water readings are abnormal or a different product is involved. The result does not authorize an application method or establish when swimming is safe.
Sources and review scope
Sources checked October 19, 2026. Model-specific instructions are not universal guidance. No independent professional review is claimed.
- ARM & HAMMER: Alkalinity First product chart. Publication date not stated.
Related calculators and guides
- Start with measured water dimensions: Pool Volume Calculator.
- Choose a supported water-planning tool: Pool Chemical Calculator.
- Keep a dated water-testing and service record: Pool Maintenance Guide.
FAQ
Can it lower alkalinity?
No. A current reading at or above target gives zero additional product. Lowering chemistry is not modeled.
Why is there no pH result?
A change in pH cannot be inferred from this linear total-alkalinity table alone.