Three types of chemicals -- chlorine, shock and algaecide -- are the basic chemicals used to maintain crystal clear pool water. Use a pool water test kit to test your water often to determine when you need to add more chemicals. Measure the amount of free chlorine, pH and alkalinity of the water with your test kit. Refer to the guide on the test kit for the ideal level of chemicals. If your chemicals measure outside the ideal range, make adjustments. The amounts of chemicals that need to be added are based on the readings on the test kit and the size of your pool.
Sanitize your water using chlorine sticks or pucks. These are a long-lasting chlorine sanitizer that are placed in a chlorinator attached to the pool pump or in a floating chlorinator. They will dissolve slowly and help maintain proper chlorine levels in your pool. Maintain 3 to 5 parts per million of free chlorine in your pool water. BioGuard Silk Smart Sticks are one available brand of sanitizer.
Chlorine shock maintains proper chlorine levels in pool water. Shock oxidizes, buffers and clarifies the water. Regular shock treatments will prevent and kill bacteria growth. Shock treatments may be needed upon opening your pool, after a heavy rain or before and after many swimmers have been in the water.
Algaecide will prevent the growth of algae in your pool. Algaecide is a liquid treatment that should normally be used on a weekly basis. Increase the frequency of treatments when outside temperatures are high.