There is no clear answer to this question. It always depends on the size of the pool, the strength of the pump, the number of people bathing in the pool, the outside temperature, the amount of rainfall, etc. The saltwater system produces chlorine, but the other water parameters (pH, hardness - calcium and other minerals, alkalinity) are not affected by the saltwater system. We always recommend that you measure the water values with test strips the first time you fill the pool and before starting any equipment, so that you know what parameters you are working from. Test the water more frequently at first and adjust the filtration time or saltwater system time. If necessary, treat the water with pool chemicals.