Add
How much salt does a pool need?
Salt is easy to calculate because it does not react with anything: to raise salt by 1,000 ppm you need 1 kg of salt for every 1,000 liters, or about 83 lb per 10,000 gallons. A new 15,000-gallon pool going from 0 to 3,200 ppm needs about 400 lb, ten 40 lb bags. After that, you only top up what is lost through splash-out, backwashing and rain dilution.
Adding salt the right way
- Use pure pool salt (99% sodium chloride or more), without iodine or anti-caking agents, which can stain.
- Turn the salt cell off while adding salt and for about 24 hours afterwards, until it is fully dissolved.
- Pour it into the shallow end and brush it toward the main drain. Never dump it into the skimmer.
- Add a little less than calculated if you are not sure of your volume. You can always add more; removing salt means draining water.
Why is my salt reading low even though I added salt?
Salt test strips and cell readings can be off by several hundred ppm, and cells read low when they need cleaning or when the water is cold. Before adding a lot of salt, confirm with a second test method. Also check the stabilizer level with the CYA calculator: saltwater pools generally need 60–80 ppm to protect the chlorine the cell produces.
Sources and methodology
Last reviewed: November 2026. Doses are calculated from the chemistry of each product (molecular weights and available chlorine) and cross-checked against manufacturer and industry dosing charts. Recommended ranges follow CDC guidance for home pools and hot tubs.
Frequently asked questions
How many bags of salt does a 15,000 gallon pool need?
Going from 0 to 3,200 ppm in 15,000 gallons takes about 400 lb of salt, or ten 40 lb bags. Most refills only need a few bags.
What salt level should my pool be?
Most salt chlorine generators want 2,700–3,400 ppm, often 3,200 ppm. Check your cell's manual: the right number is the one your manufacturer specifies.
What kind of salt should I use?
Pure sodium chloride (99%+) labeled for pools. Avoid salt with anti-caking agents or iodine, which can stain.
How do I lower salt if I added too much?
The only way is to replace water: drain part of the pool and refill with fresh water. This calculator tells you how much to drain.