Hello all – here is a summary of my current conundrum.
This is a new pool – completed in November 2012.
Up until now my CH numbers have been consistent at 300-330 (using my TFT100), even though the three pool stores that I visit for monthly comparison have showed me at 230-260. Same for my TA, small changes being occasionally made to a tee using my spreadsheet and the pool calculator.
Here were my numbers last weekend:
TC/FC = 4.5 (taken in the morning)
pH = 7.5
TA = 70
CH = 300
CYA = 35
Borates = 50
I added 16oz of baking soda which I would expect to bring up TA by around 4 according to the pool calculator. I also added 19oz of CYA which I expected to raise CYA by about 8, which appears to have occured
Today I test and I have the following numbers (measured twice just to confirm)
TC/FC = 3.5 (taken in the afternoon)
pH = 7.8
TA = 90
CH = 140
CYA = 45
Borates = 50
1) Any thoughts on what would have consumed over ½ of my calcium?
2) Any thoughts on the large jump in TA?
If somehow ½ of my water was to have been replaced than I would think that my chlorine would plummet since I am on a scheduled 1ppm dose each night with my stenner pump. That has not happened.
Do I dare add calcium since I am below 200?
Thanks for reading!