Bicarb Start-up


Well-known member
Mar 7, 2012
Mountain Brook, AL
This is a topic I'm very interested in as I'm on day 4 of new plaster. I have read here several times not to worry about CH and TA as they will rise on their own, then adjust them after a few weeks. I'm wondering if raising the CH to 200 is a good idea as onBalance suggests. I didn't acid wash and it seems that the hard troweling was done well. I do think most of the same plaster dust gets swept around over and over. It seems to settle right away. I've backwashed twice.

Day 4
FC 1.0
Ph 7.2
TA 60
CH 170

chem geek

TFP Expert
LifeTime Supporter
Mar 28, 2007
San Rafael, CA USA
Re: The Bicarb Start-up and Why it Works

At a minimum, I'd get your pH and TA up as well as your CH to some degree. If you went to 7.8 in pH, 80 ppm in TA, and 200 ppm in CH, then at least your saturation index will be slightly positive. For your 13,500 gallon pool that would be 20 ounces volume of soda ash (sodium carbonate aka pH Up) and 20 ounces volume of baking soda (sodium bicarbonate aka Alkalinity Up) and 6 cups of calcium chloride anhydrous (11-1/2 cups of calcium chloride dihydrate).

If at that point you only find the pH to rise but the CH remains stable, then you'll know that you are protecting your plaster. In that case, the CH could be raised even more since eventually you'll probably have it at 300 ppm if you intend to keep your pH around 7.5.