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.
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.
Want the numbers worked out for you? Enter your pool volume and test results in our pool chemical calculator to see every dose in one check.
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.
Related calculators and guides
- Calculate pool volume in litres
- Chlorine dosage calculator (maintenance dosing)
- Full pool chemical calculator
- Pool alkalinity calculator (check TA after shocking)
- Pool salt calculator (saltwater chlorinators)
- Spring pool opening checklist
- Chlorine doses for small and above ground pools
- Green pool after rain guide