If you rely on chlorine for sanitizing your pool you should have a steady level of 1.0-3.0 ppm (parts per million) of chlorine in your pool. You can add this in several ways. You can install an automatic chlorinator that takes tablets, either 1″ or 3″ that are added to your water as it flows through your system. You can add liquid chlorine (which is the fastest acting version of chlorine, it is also the most quickly used up by your pool). You can can also add granular shock chlorine products to the pool, or in some cases use a floating chlorine dispenser. The rule of thumb for adding chlorine is 1 bag of shock or gallon per 10,000 gallons of pool water. You can adjust and add more if the pool is green or cloudy. At openings we typically add 1 case (4 gallons) of liquid chlorine to all pools, and 2-3 cases for low water clarity, green, or in general really dirty/algae filled pools.
Another popular option is to install a chlorine generating cell/salt system to your pool. This uses regular salt, the cell converts the salt into the sodium and chlorine atoms, and the chlorine sanitizes your pool. It will then convert back into salt and maintain a healthy level in the pool until it is converted again, and helps to keep the pool clean.
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