Filled pool up test results show high hardness?

[12mustangdude]

Filled 18k gallon swimming pool up and here is what I'm showing test wise

2.43 free chlorine
4.48 total chlorine
7.9 ph
91 total alkalinity
446 calcium hardness
4 stabilizer.

What could be causing such a high hardness? Pool is dirty though with bugs and leaves gonna let robot do its thing tommorow and retest. Should I be concerned?

 

[Richard320]

More than likely, tester error. Those look like the results from a digital tester. They don't seem to stay in calibration from what I've read here over the years. What are you using to test?

The other possibility is that you have extremely hard water. Do you have white crust on your showerheads and in the coffeemaker? Scale lines at the water level in the toilet bowl?

 

[12mustangdude]

You are correct using a LaMotte 2056 I bought new off amazon.

Haven't used any of the items mentioned but they all dried off from previous owners, there is crust on showerheads and scale lines from toilet bowl, neither has been ran in a good 4 months or so.

 

[Isaac-1]

I would tend to guess tester error, a search of the forum here will show many threads about problems with the LaMotte digital tester, several are from people that started off liking them but over time came to realize that their results were unreliable. The problem seems to be that it may work good for a while then consistently give bad readings. Although it is possible you have very hard fill water, since the type of geology varies considerably around the metroplex. In general we tend to see very high CH fill water mostly in the South West US, say west Texas to California.

 

[duraleigh]

More important than your CH is the spread between FC and TC........
That's too much if you believe that digital tester (we don't like them)

If that spread is confirmed, you will need to SLAM your pool.

read "The ABC's of Pool Water Chemistry" up in Pool School and then read "How to SLAM Your Pool".

We'll help you get that straightened out but it is a bigger problem than your CH that can be addressed once you solve the chlorine problem.

 

[12mustangdude]

new test after slamming pool and waiting an hour.

1.02 free chlorine
3.77 total chlorine
7.6 ph
126 alkalinity
191 calcium hardness
21 stabilizer.

Think the chlorine messed up since I forgot to add any between tests

 

[anonapersona]

Free chlorine would drop and total chlorine would drop and the difference which is combined chlorine could get higher. But none of that would have affected the CH or the TA.

Makes me wonder what two tests only 30 minutes apart might tell. Be sure to get the water sample when the pool has been running for an hour or more and sample from 18" or more below the water surface. I am suspecting the testing is wacky.

 

[12mustangdude]

Pool has been running for nonstop will try to get 2 tests 30 mins apart. Should I shock again tommorow?

 

[duraleigh]

For clarity, we teach to SLAM a pool, not "shock" it.

The spread between your FC and TC indicates the need to SLAM the pool. read "The ABC's of Pool Water Chemistry" up in Pool School.........it seems you need a better understanding of cc's. That's the difference between FC and TC and, if they exceed .5 ppm (yours do) then you need to SLAM.

Then, read "How to SLAM Your Pool" up in Pool School. We'll help you with the process but you must understand it is a process......not a one-time dosage.

Your LaMotte tester is not helping you. Rather than trying to do this work with a testing device that is not up to speed, I hope you consider one of the drops based testing kits we suggest which will give you the accuracy, precision and repeatability that you need.