Types of Shock

• Chlorine shock comes in two different forms that include liquid shock and granulated shock that must be predissolved before adding it to the water. If the granulated shock is not dissolved first, it will stain a vinyl pool liner of an above ground pool. Liquid shock is ready to use right out of the bottle and is sold in gallon sizes. The shock can be applied directly to the water.
  
  

How Much Shock

• Shock must be added in increments of 5,500 gallons. One gallon of liquid shock and one treatment of granulated shock treats up to 5,500 gallons of water. Therefore, to treat a pool with 10,000 gallons of pool water, you will need to use two gallons of shock. If you are unsure about your pool's capacity, use an online pool volume calculator to calculate the water volume based on your pool's dimensions (see Resources).
  
  

When to Shock

• One treatment of shock should be used when you open the pool for the season and just prior to preparing to winterize the pool (closing) for the season. As a course of maintenance, you should add a treatment of shock somewhere in the middle of the pool season. In times of cloudy pool water, which can occur after heavy usage, a rain storm or during the early stages of algae growth, shock treatment is also recommended.
  
  

How to Shock

• Shock is added directly to the water around the edges of the pool. Run the filter for 24 hours after adding shock to have the chemicals circulated throughout the pool, which increases its effectiveness. Due to the strength of the shock, no one should swim in the pool for at least six hours after the shock is added. Never add shock through the pool skimmer.