Pool Shock Calculator Australia
Estimate a chlorine increase from pool volume and product strength. The chart shows 12.5% liquid chlorine first and 70% calcium hypochlorite second; subtract your measured free chlorine from the intended target.
Use your actual pool readingsOpen the calculator for a dose based on pool type, volume, and current test result.Decide whether shocking is actually needed
- Test free chlorine, combined chlorine, pH, and water clarity before adding product.
- Shock targets depend on the problem, CYA level, product label, and pool system—there is no safe one-dose-fits-all target.
- For routine sanitation, use the normal calculator rather than automatically applying a shock dose.
Australian dose chart
Each cell shows 12.5% liquid chlorine / 70% cal-hypo. These are strength-based estimates for the stated ppm increase, not a substitute for the product label.
| Pool volume | Raise free chlorine by 5 ppm | Raise free chlorine by 10 ppm |
|---|---|---|
| 30,000 L | 1.2 L / 215 g | 2.4 L / 430 g |
| 50,000 L | 2.0 L / 360 g | 4.0 L / 715 g |
| 75,000 L | 3.0 L / 535 g | 6.0 L / 1.1 kg |
| 100,000 L | 4.0 L / 715 g | 8.0 L / 1.45 kg |
How to dose without overshooting
- Confirm pool litres first; use the volume calculator if the capacity is uncertain.
- Measure current free chlorine and choose a target supported by the product label or a pool professional.
- Calculate only the ppm increase required and verify the product concentration.
- With nobody in the water, add the product exactly as its label directs and keep circulation running.
- Retest free chlorine and pH before swimming; reopen only when the label’s re-entry conditions are met and the water is clear.
Safety and system checks
- Never mix liquid chlorine with calcium hypochlorite, acid, or any other pool chemical.
- Cal-hypo also adds calcium; consider liquid chlorine when calcium hardness is already high.
- Naked freshwater systems advise against granular chlorine; follow the system manufacturer.