Hardness Test Kit

Hardness Test Kit

Calcium hardness is the third important test to keep your water balanced, with ph and total alkalinity being the other two. When testing pool water for calcium hardness, what you are really measuring is how soft or hard water your swimming pool water is at any given moment.  Pool water where the hardness level is too high or low contributes to a pool that has unbalanced water.

Pool water with calcium hardness too low might appear sparkling clear, when in reality the water is actively corroding surfaces of your pool.  This is one reason to test your pool, even when the water is clear and appears balanced and healthy.

Fortunately, calcium hardness in pool water usually does not change rapidly over short periods of time, so only occasional testing is really needed.  A monthly hardness test is usually recommended, or any time you make major changes to the pool water like draining the pool and adding fresh water back in.