how to decrease hard water in pool
Reduce Pool Water Hardness. 1  Take a water sample from a depth of at least 12 inches from the water surface. 2  Add a reagent from a hardness test kit to the water sample and check the result against the guide provided by the test kit manufacturer. 3  Drain some of the water in the pool if the water hardness level is too high. Add fresh water to replace the water you remove from the pool. Collect another sample of the pool water and conduct the hardness test again to check that the hardness is between 200 to 400 ppm.