What target salinity should I use?
Use the target for your exact chlorinator model and a verified current reading. This calculator deliberately leaves the target blank.
Pool Salt Calculator
Plan additional salt from a measured water volume, current salinity and the target specified for your chlorinator. No universal salinity target is selected for you.
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.
Use a current salinity reading and the correct manual
Check the salt requirement for your exact chlorinator and confirm the measurement unit. A saltwater pool is still a disinfected pool; a salt reading does not replace a free-chlorine or pH test. An unexpected reading deserves verification before estimating another addition. The referenced Hayward manual is an example for one system, not a target for every brand.
Required mass is not the same as bags to buy
The calculator estimates dry sodium chloride equivalent. It rounds only the purchase quantity up to whole bags. Buying two bags does not mean adding both bags. Products containing other ingredients or substantially different purity are outside this simplified model; use the equipment and product instructions rather than substituting a percentage without a supported model.
Salt-planning arithmetic example
These entered readings illustrate arithmetic, not a recommended target. At 20,000 L, a change from 1,000 to 3,000 ppm corresponds to 40 kg of dry NaCl equivalent.
| Input or result | Example |
|---|---|
| Pool water | 20,000 L |
| Entered concentration increase | 2,000 ppm |
| Required mass | 40 kg / about 88.18 lb |
| Package | 25 kg per bag |
| Purchase | 2 bags; 50 kg purchased, not 50 kg required |
What if salinity is already above target?
The additional amount is zero. The calculator does not diagnose a sensor error or recommend draining. Confirm the reading and ask the equipment manufacturer or a qualified service provider about the appropriate response. Water removal can introduce structural and environmental risks beyond a salt calculation.
Methodology and limits
Estimated kilograms = liters x positive salinity increase in ppm / 1,000,000. This uses the dilute-water approximation that ppm is mg/L and assumes 100% dry NaCl equivalent. Volume, test accuracy, dissolved material and product composition affect the real result. This is a quantity estimate, not mixing, application or commissioning instructions. Follow the current product label and chlorinator manual.
Sources and review scope
Sources checked October 19, 2026. Model-specific instructions are not universal guidance. No independent professional review is claimed.
- Hayward Salt & Swim 3C: salt requirements. Manual 092527 Rev C; 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.
- Separate salt readings from the rest of pool care: Saltwater Pool Maintenance Guide.
- Compare ongoing expenses: Saltwater vs. Chlorine Pool Cost.
FAQ
Does saltwater replace chlorine?
No. A salt chlorinator produces disinfectant from salt; water testing and equipment-specific maintenance remain necessary.
Why are purchased bags heavier than the calculated amount?
Bags are indivisible purchases. The remaining material is not part of the calculated addition.