Newly Plastered Pool Closing Chemistry


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Bronze Supporter
Jun 15, 2017
East Coventry, PA
Our pool was just replastered with Wet Edge quartz based plaster on October 26. We have been brushing and balancing since. Tomorrow the pool folks come to close the pool for the winter. I have been working hard but trying not to cause extreme changes in water chemistry, but the pH is as low as I can bring it, the Alkalinity is still to high and the CSI close to too low:

FC. 2
CC. 0
pH. 7.2
CH 275
Alkalinity 110
Temp. 50F
CSI. -0.55

can anyone lend some advice on what I can do to adequately prepare for the closing and winter? I tried to call WetEdge but of course they are closed this week.

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
With new plaster, you need to let the pH rise up. A CSI of -0.55 is much too low. Don't try to adjust the TA at this time. Go ahead and close. The pH should rise up into the 8.0 - 8.5 range to help counterbalance the effects of cold water. Open as soon as you can to brush the plaster and rebalance. Unless you are relying on Polyquat 60 as insurance, make sure to increase the FC to about SLAM level before closing to prevent algae.
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