Calcium high


May 26, 2015
PH 7.2
Chlorine 7.5
Calcium 1100
Alkalinity 120
CYA 80

Should I be concerned about calcium being so high? Our in coming water is 400.

Any suggestions?

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Many areas in the Southwest are notorious for having high CH levels. To help compensate, it is imperative that you continue to counterbalance that high CH with a low pH and TA. You've done that with the pH, but your TA could be lowered a bit as well. This will also help keep your "CSI" level in a relatively safe zone as noted on the Poolmath calculator which will help to prevent scale build-up. Your CSI is at about "0.3" right now which is good because your pH is on the low side. If your pH increased to just 7.5, your CSI would shoot-up to 0.58 which is at the 0.6 limit for potential scale. So you're doing well with the lower pH. With your current pH of 7.2, if you lowered your TA as well to about 60, your CSI would almost be neutral at -0.1. So keep an eye on your pH and TA and watch how they effect your CSI level on the Poolmath calculator to ensure the CSI doesn't creep-up over 0.6. Have a nice day.
Pool School - Lower Total Alkalinity


Well-known member
May 17, 2016
Phoenix, AZ
Typical for Arizona.
Keep you pH down to keep your CSI number low.
You can check the CH level of your fill water and, if low, you can drain and refill your pool when it cools down or get RO done.