For routine maintenance, a common rule is 1 pound of pool shock per 10,000 gallons of water. Some products use different dosing, so the safest move is to match the amount to your pool’s volume and the label on your specific shock product.

Simple rule

  • 5,000 gallons: about 0.5 pound.
  • 10,000 gallons: about 1 pound.
  • 15,000 gallons: about 1.5 pounds.
  • 20,000 gallons: about 2 pounds.

When to add more

If the water is cloudy, green, or you suspect algae, you may need more than the normal maintenance dose. Product labels vary a lot, and some shock brands are stronger or weaker than others, so the package directions should win over any general rule.

Best practice

  • Test your water first.
  • Use your pool volume in gallons.
  • Follow the exact dosage on the shock package.
  • Add shock at night if possible so sunlight does not burn it off as fast.

Example

If your pool holds 21,000 gallons and the product says 1 pound per 13,500 gallons, you would round up to about 2 pounds.

Safety note

Do not swim until chlorine levels are back in the safe range, typically 1–4 ppm.