CH Drifting Upward

[Kit]

The CH in my in-ground gunnite spa has been relatively stable over the years. However, in the past few months I noticed that the reading drops from 300ppm to 250ppm weekly. All the other chemistry levels are fine. What might be causing this?

I have been purchasing Calcium Hardness Increaser by Clorox & was wondering if there might be a less expensive alternative. Thank you for your help.

 

[ajw22]

Do you have an autofill in your pool?

CH drops due to leaks.

Is your CYA and Salt also dropping?

 

[Kit]

ajw22: Sorry for the response relay. Yes, I have an autofill. Since my SWCG has been disconnected for several months during the winter season, I have not been checking my salt level. I've just been adding chlorine bleach as needed. However, I checked my CYA level today & it was below 20. I added stabilizer today & will recheck tomorrow. Might this be causing the drops in CH?

 

[ajw22]

ajw22: Sorry for the response relay. Yes, I have an autofill. Since my SWCG has been disconnected for several months during the winter season, I have not been checking my salt level. I've just been adding chlorine bleach as needed. However, I checked my CYA level today & it was below 20. I added stabilizer today & will recheck tomorrow. Might this be causing the drops in CH?

Nope.