Calcium Hardness Increase and the Pool Calculator

[benavidescj]

I drained over half my pool a few days ago to get my CH down some because it was at 630ppm. Well I overshot the drain and when I did a test (Taylor K-2006) it was at 110ppm (11 drops). My fill water is 70ppm. Anyways, I wanted to get back up to around 200ppm but I wanted to do it slow so I started with 10lbs calcium chloride. Adding 10lbs should have brought me up to around 150ppm per the pool calculator. Checked it today and low and behold it came out to 320ppm (32 drops). What happened? Is there something wrong with my calculation or is there something wrong with the pool calculator? I let the water mix one day when I did the refill and waited another day after adding the calcium chloride before testing.

 

[JasonLion]

Most likely your new fill water and your original pool water did not thoroughly mix and when you did the test that showed CH of 110 you were testing mostly new fill water that only had a little pool water mixed into it. I suggest leaving the pump running for 24 hours to really throughly mix everything and then measure CH again.

 

[benavidescj]

Makes sense to me. Thought a full day at 24/7 would have mixed it well. As it turns out 320 ppm is in the sweet spot. What is odd is the salt level was at 1600ppm and the calculator told me to put in 11 - 40lb bags of salt to get to 3400. It hit right on the money at 3400 ppm.

 

[Brentr]

Carlos, it appears that we have very hard water in Jacksonville. After 2 partial drains 2 mths ago I went from 775 to 400 however it is back up to 475. If I were you I would let it rise slowly because you will get out of range soon.