How much salt to add to reach your salt-chlorine generator’s target — or how much water to drain to bring a high salt level back down.
Most generators run best at 2,700–3,400 ppm (≈3,200 ideal). Always defer to your unit’s manual.
Add this much pool salt
534 lb (≈ 13.3 × 40-lb bags)
to raise salt from 0 to 3,200 ppm in 20,000 gal
(target − current) × gal × 8.34 ÷ 1,000,000 → (3,200 − 0) × 20,000 × 8.34 ÷ 1,000,000
8.34 = weight (lb) of 1 US gallon of water.
Use pool-grade salt (≥99% pure NaCl, non-iodized, no additives). Broadcast it over the pool — never down the skimmer.
Brush to dissolve, run the pump ~24h, then re-test. Add in stages — salt only comes down by draining, so don’t overshoot.
A “saltwater” pool isn’t chlorine-free — it makes its own chlorine. Dissolved salt (sodium chloride) flows through a salt chlorine generator, where an electrified cell splits it into chlorine that sanitizes the water and then recombines back into salt. Because the salt is recycled rather than consumed, you don’t dose it daily like chlorine. You set the level once, and it only drifts when water physically leaves the pool — splash-out, backwashing the filter, draining for winter, or a leak — or gets diluted by heavy rain and top-offs. That is why this calculator’s job is usually a one-time correction, not a routine chore.
Use only salt sold for pools or water softeners — pure, non-iodized sodium chloride, with no anti-caking or yellow-prussiate additives that can stain. Enter your pool volume and current salt reading above, and the calculator tells you exactly how many pounds (or bags) to add to reach your target. Pour it across the deep end with the pump running, brush any piles off the bottom so they dissolve instead of sitting on plaster, and run the pump for 24 hours before you trust a re-test. Hold off on running the salt cell until the salt has fully dissolved and mixed. If you’re lowering an over-salted pool, there’s no chemical that removes salt — you dilute it by draining and refilling, and the calculator shows roughly how much water to swap to hit your number.
Pounds of salt = (target − current ppm) × gallons × 8.34 ÷ 1,000,000. For example, a 10,000-gallon pool starting at 0 needs about 267 lb (six to seven 40-lb bags) to reach 3,200 ppm. Enter your volume and levels above and the calculator works it out exactly.
Most salt-chlorine generators want 2,700–3,400 ppm, with about 3,200 ppm ideal. Brands vary slightly — Hayward AquaRite ~3,200, Pentair IntelliChlor ~3,400, Jandy AquaPure ~4,000 — so check your unit’s manual. Below ~2,700 ppm the generator slows or stops; too high can taste salty and trip a high-salt shutdown.
There’s no chemical that removes salt — you lower it by dilution. Drain a fraction equal to 1 − (target ÷ current) and refill with fresh water. Use the “Lower salt” mode for the exact gallons. Note this also lowers CYA, alkalinity, and calcium, so re-test afterward.
Use pool-grade salt — sodium chloride that’s at least 99% pure, non-iodized, with no anti-caking or yellow-prussiate additives. It’s the same idea as water-softener salt but cleaner; avoid rock salt or table salt.
Broadcast it across the deep end (never down the skimmer), brush it around to help it dissolve, and run the pump for about 24 hours before testing. Adding it in stages and re-testing keeps you from overshooting — since the only way down is draining.
Salt-chlorine generators need enough salt to run; below roughly 2,700 ppm most reduce output or shut off and flash a low-salt warning. Cold water also lowers readings. Add salt to your target and the cell should resume — but confirm with an independent salt test, as cell readings drift as they age.
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