Back-Washing - Calcium Hardness not going down???

LaROckl

Active member
Aug 12, 2018
33
New Orleans, LA
Newly re-plastered pool (plaster stripped to gunite) the pool was done about 10/12 weeks ago... then about 3 weeks ago ...Switched to Salt from FW.

Over the past three (3) weeks I've done some fairly heavy back-washing to bring the Cyanuric Acid level down... which it has done. We have enough rain here (New Orleans) that I almost *never* add city/tap water to the pool... i.e., all back-washing is co-ordinated with rainfall.

I'm still on a learning curve here... and, my question is: Salt (which, I've replenished) & Cyanuric Acid (now @ desired level) were reduced via back-washing but the Calcium Hardness has remained steady? What's up with that?

Thanks!

dennis

Pool ChemistryNew Sand Filter
add Salt
(Last Shock)Heavy BWBWBW
Test Date26-May
2-Jun​
8-Jun​
16-Jun​
Salt3300310030003300
(3100)(2900)(2900)(3200)
Free Chlorine3.03.04.05.0
pH7.27.67.47.6
Cyanuric Acid100858075
Total Alkalinity70908090
Calcium Hardness280280280280
Metals0000
 

zea3

Mod Squad
TFP Expert
LifeTime Supporter
Jul 10, 2009
11,726
Houston, Texas
As new plaster cures, pH and CH tend to go up. This process can take up to a year to stabilize. Just keep an eye on both levels and adjust as needed.
 

LaROckl

Active member
Aug 12, 2018
33
New Orleans, LA
Thanks!!! makes sense... I'm adding about a gallon of Muriatic Acid per week to keep the pH in check. Guess I'll go get the parts and build an acid feeder today.

thanks again!!!!

dennis