Shock the pool
Into 21,100 gal of water, add
6.40qt 6.06LHASA CHLOR — sodium hypochlorite, 12.5%. Free chlorine from 0.5 ppm to 10.0 ppm.
Your pool
The answer, the drawings, every reading and every table on this page are worked for the values in these fields, and worked again as you type. The questions further down are answered for the example this page was published with.
Every product that does this
| Product | Add | Also moves |
|---|---|---|
| HASA CHLOR sodium hypochlorite 12.5% |
6.40 qt 6.06 L |
nothing else measured |
| Multi-Chlor sodium hypochlorite 12.5% |
6.40 qt 6.06 L |
nothing else measured |
| Pool Shock Calcium Hypochlorite 65% calcium hypochlorite 65.0% |
2.57 lb 1.17 kg |
nothing else measured |
The manufacturer's own dose sentence reads: 10 fluid ounces per 10,000 gallons. The figures above are computed from the product's strength.
In steps, if you would rather
| To reach | Add | Total added |
|---|---|---|
| 2.4 ppm | 1.28 qt | 1.28 qt |
| 4.3 ppm | 1.28 qt | 2.56 qt |
| 6.2 ppm | 1.28 qt | 3.84 qt |
| 8.1 ppm | 1.28 qt | 5.12 qt |
| 10.0 ppm | 1.28 qt | 6.40 qt |
Where the band comes from
| Source | Range |
|---|---|
| Florida 64E-9.004 (1)(d)2 conventional pool |
1.0–10.0 ppm |
| Florida 64E-9.004 (1)(d)2 spa or hot tub |
2.0–5.0 ppm |
| Florida 64E-9.004 (1)(d)2 indoor pool |
up to 5.0 ppm |
| CDC Healthy Swimming stabilised pool |
2.0 and up ppm |
Pool and spa rules are adopted and amended state by state, and most of the ranges here are written for public pools. Confirm every figure against the code your jurisdiction has adopted and against your own product label.
What people ask
How many pounds of shock for a 21,100 gal pool?
How much does one pound of shock raise chlorine?
Other adjustments
- raise Salt, and how to raise it
- lower How to lower pH
- raise Total alkalinity, and how to raise it
- raise How to raise pH
- raise How to raise Free chlorine
- lower Lower total alkalinity
- raise How to raise Stabiliser
- raise Raise calcium hardness
Updated September 2026
Sources and dates
Ranges are quoted from the code named beside them, product strengths from the manufacturer's own product page, each retrieved on the date shown.
- Florida 64E-9.004 (1)(d)2 · http://flrules.elaws.us/fac/64e-9.004 · 2026-09-17
- HASA · https://hasa.com/pool-chemical-calculator · 2026-09-17
- CDC Healthy Swimming · https://www.cdc.gov/healthy-swimming/about/home-pool-and-hot-tub-water-treatment-and-testing.html · 2026-09-17
- HASA CHLOR · https://hasa.com/product/hasachlor · 2026-09-17
- Multi-Chlor · https://hasa.com/products/ · 2026-09-17
- Pool Shock Calcium Hypochlorite 65% · https://pyrockchemical.com/products/pool-shock-calcium-hypochlorite-65-for-sale · 2026-09-17