Pool Shock Calculator
Pool Shock Calculator
Pool Shock Calculator
Enter your pool size, select your calcium hypochlorite strength, and choose whether you are doing a normal shock or treating algae / problem water.
How many gallons are in my pool?
Not sure how many gallons are in your pool? Enter your pool dimensions in our Pool Size Calculator to estimate your pool size in gallons.
Recommended Pool Shock Products
Choose the product that matches your strength and package size:
Maintaining proper chlorine levels is essential for keeping swimming pool water clean and safe. Our pool shock calculator helps determine how much calcium hypochlorite pool shock you need based on your pool size, product strength, and water condition.
How to Use This Pool Shock Calculator
Enter your pool size in gallons, then choose whether you are using 56% or 68% calcium hypochlorite. Next, choose whether you are doing a normal maintenance shock or treating algae, cloudy water, or other problem water conditions.
This calculator will estimate the total pounds of pool shock needed and approximately how many 1 lb bags to use.
Pool Shock Dosage Guide
The general rule used by most pool professionals is:
1 pound of pool shock per 10,000 gallons of pool water for 68% calcium hypochlorite under normal conditions.
Because 56% calcium hypochlorite has lower available chlorine, it requires slightly more product to achieve the same sanitizing effect. Pools with algae or severe water quality issues often require double the normal dose.
| Pool Size | 68% Normal Shock | 56% Normal Shock | 68% Algae / Problem Water | 56% Algae / Problem Water |
|---|---|---|---|---|
| 10,000 gallons | 1.00 lb | 1.21 lb | 2.00 lb | 2.43 lb |
| 20,000 gallons | 2.00 lb | 2.43 lb | 4.00 lb | 4.86 lb |
| 30,000 gallons | 3.00 lb | 3.64 lb | 6.00 lb | 7.29 lb |
When to Use Algae / Problem Water Dosing
- Visible algae growth
- Cloudy or dull pool water
- Heavy swimmer usage
- Storm debris or contamination
- Very low chlorine levels
- Strong chlorine odor caused by chloramines
Under these conditions, many pool professionals use a stronger shock treatment to restore water clarity and sanitation more quickly.
Tip: For best results, shock your pool at night while the pump is running so the chlorine can circulate properly and sunlight does not reduce effectiveness.
Not sure whether to use chlorine tablets or pool shock? Learn the key differences between chlorine tablets and pool shock.