Saturation index off the charts after lots of rain

Foonly

Well-known member
May 24, 2018
45
St Augustine FL
My history of measurements is in my TFP profile. Suddenly after several days of rain, my CSI is down to -0.52 and I need guidance on which factor to correct first. I have had to drain about 1.5 inches of water out of the pool, and add 10 lbs of salt. None of the numbers look unusual except for their cumulative effect in the CSI. The only number outside the TFP guide is CH and I have been advised here not to try to bring that up right away but maybe now is the time.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
22,426
Laughlin, NV
You need to track your SALT in Poolmath to accurately create CSI. I do not see a SALT reading in your log.

Your pH will rise which will raise your CSI.
Do not aggressively lower pH in the future. At most, drop it to 7.6 when it hits 8.
Your CYA could not increase from 70 to 80 unless you added CYA to the water.
 

Foonly

Well-known member
May 24, 2018
45
St Augustine FL
Thank you. I have updated some recent log entries to record salt levels (from my spreadsheet I use for plotting) and turned on tracking for it.. Salt level was staying steady at 3100 until this recent pattern of daily thunderstorms. I will change my goal pH higher, I was just going by the range the TFP app gave me of 7.2-7.8. Is there a way I can change that in the app? I did not add any acid today so it should come up - it rises pretty quickly left to itself. The CYA measurement is a bit difficult for me to judge exactly when does the black dot dissapear.
The SWG display and the Taylor chemical test give the same values for Salt. It was 3100 this morning but now it is 3000 so I put in some more.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
22,426
Laughlin, NV
In the app you will need to adjust your Target each time if different than what the app selects.

When you do the CYA test, try this next time.

Once you have your solution ready, back to the sun, etc. Fill the vial to a line, say 80, lower the vial to your waist level and glance for the dot, you see it, add solution to the 70 line, glance, see it, repeat until you no longer see it with a glance. Then use the CYA value one step above the line you read. So if you stopped at 50, use 60 ppm CYA.

The vial is in logarithmic scale. So it is not viable to interpolate between the lines. Just use the whole numbers, such as 50, 40, 30, ....