Salt water would create soft water in your pool. You should follow the manufacturer directions and recommendations for the proper amount of salt in your pool, typically 2700-3400ppm (parts per million) for your salt cell to work properly.
When you are initially adding salt to a pool, it will take 15-20 bags of salt (at 40lbs) each to gain the residual amount that you need.
Once the pool is operational, you will add new salt as you add new water, when water is splashed out, or your have backwashed your system and require new water. Typically then you will add one bag at a time, and monitor your system to find out when the water is again at the proper level.
There are also test strips and electronic water chemistry readers that will help you test the levels if you are unsure.
Remember if you have a salt pool, you MUST have a ZINC ANODE in your pool system or pool itself to help with corrosion.
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