How to use disinfect pool water using Champion Pool Shock 12.5%: For a new pool or for spring start up, superchlorinate with (64 to 128 oz.) on 10% pool shock or (52 to 104 oz.) on 12.5% pool shock for each 10,000 gallons of water to yield 5 to 10 PPM available chlorine by weight. Check the level of available chlorine with a test kit. Adjust and maintain pool water pH to between 7.2 to 7.6 and alkalinity between 50 to 100 PPM.