Big jump in Calcium Hardness

Spgull

Silver Supporter
Apr 23, 2017
11
Estero,FL
Hi All
Just wondering why my CH would go
from 320 to 650 when it has never been higher than 350? We haven’t much rain yet so I’ve had to use fill water which when tested with Taylor k-2006 is 40. Not sure if that’s good or bad. I’ve had to lower my PH to compensate for the high CH to keep my CSI in check. Should I drain a little water or just leave it alone?
Thanks
FC 6
PH 7.3
TA 70
CH 650
CYA 50
Temp 87
CSI -0.03
 

wireform

Silver Supporter
In The Industry
Aug 15, 2017
1,304
Spring Valley, NY
Did you use the correct amount of pool water in the vial. You may have used the the vial labeled CHLORINE and that is to be used only for the FC level. Residue left over can screw with the results.
 

tim5055

Mod Squad
TFP Expert
LifeTime Supporter
May 11, 2014
10,923
Franklin, NC
2.5 gal jug 10.5% from pool store. Fresh jug. I have used their product for several years without any problems.
Well, that kills the thought that yo had been using CalHypo granular chlorine. Calcium has to be added for the amount in the water to go up or there was a testing error. Using fill water with a CH of 40 it would take a long time to double the amount in your pool.
 

Spgull

Silver Supporter
Apr 23, 2017
11
Estero,FL
Thanks for your help Tim. I repeated the test several times with the same results. Long shot...I ordered a new comparitor from Taylor. Many miles on the one I’ve been using. Maybe it’s contaminated or something.
 

Spgull

Silver Supporter
Apr 23, 2017
11
Estero,FL
I did the test both ways using the 25 and 10 ml with the appropriate multipliers. Basically the same results. I also used fresh reagents from Taylor.