Pool and spa owners have long since used chlorine tablets to balance the water and keep it clean. The effects of these tablets are skin irritation, brittle hair, red eyes and allergic reaction. The chlorine level in a chemical pool is between 1 and 3 ppm, or parts per million. A saltwater system uses dissolved salt to produce chlorine at a level that is closer to 1 ppm. The result is clean and clear water without the harsh effects of chlorine tablets.
Packaged chlorine is unstable and hazardous to humans and animals. These tablets or liquid are added to the water constantly to keep it clean and safe to swim. Chlorine reacts with organic matter in swimming pools -- such as sweat, urine, blood, mucus and skin cells -- to form chloramine. These molecules are different from free chlorine and cause the chlorine to be less effective, leading to more chlorine added to the system and further irritation of the skin.
A chlorine generator is how the saltwater system works. The dissolved salt passes between two plates in the generator causing the sodium and chloride to split apart and bond with hydrogen and oxygen in the water. These molecules form HOCI, or the chlorine that cleans and sanitizes the pool water. The HOCI kills the algae and bacteria that make the water look green and then converts back to dissolved salt to begin the process again. Salt stays in the water, even if water evaporates, so the system rarely needs extra salt added. The level of salt in the water is very low, about 3,000 ppm, so low most people can not even taste the salt.
Pool water, salt or chemical, should be tested weekly for pH and free chlorine. A saltwater pool should also be tested for salinity. Sometimes the chlorine level will be low, due to heavy rain, extended use and direct sunlight. In this instance, you have two options. Option 1 is to run the boost function on you chlorine generator or run your generator for an extended period of time. This will boost the chlorine levels back to normal and keep the water safe. Option 2 is to shock the pool with the same chemicals that you would in a normal chlorine pool. This "shock" quickly adds chlorine to the water and makes it safe again.
Lower Chlorine Levels
A saltwater pool does use chlorine to clean the water. However, that chlorine is made with the salt that was dissolved into the water when the system was installed. Chlorine sticks, tablets and powders contain chemicals that are harmful in large quantities. The chlorine levels in a saltwater pool are about half of those in a chemical pool.