A salt chlorine generator makes its own chlorine from dissolved salt — but only if the salinity sits in its happy range. Too little and it won't produce; too much and you risk corrosion and an error light. Here's how much to add.
The target: about 3,200 ppm
Most saltwater systems want roughly 3,000–3,400 ppm. Aim for the middle (about 3,200) and check your generator's manual — some brands differ. It's a band, not a single number.
The formula
Pounds of salt = gallons × (target − current ppm) × 8.34 ÷ 1,000,000. For a fresh fill (0 ppm) to 3,200, that's about 27 lbs per 1,000 gallons. A 15,000-gallon pool needs roughly 400 lbs — ten 40-lb bags. The pool salt calculator does it from your exact numbers, and if you don't know your volume, start with the pool volume calculator.
How to add it safely
- Test your current salt first — you're topping up, not starting from zero, unless it's a fresh fill.
- Add salt gradually with the pump running; brush it around so it dissolves instead of piling on the bottom.
- Wait 24 hours and retest before adding more. You can't remove salt except by draining and diluting, so it's better to under-shoot and top up.
- Use pool-grade salt (99%+ pure). Avoid rock salt or water-softener salt with anti-caking additives.
Why volume accuracy matters
Every dose here is per-gallon, so a wrong volume throws off the whole calculation. Measure your pool once, write the gallons on the equipment pad, and salt (plus every other chemical) becomes simple arithmetic.