Total alkalinity is the measure of the amount of alkaline salts in the water, which give water the ability to resist changes in pH or buffer the water from wild pH swings. In water that contains no buffering ability, the pH can wander dramatically with the addition of small amounts of acids or bases (alkali), or other pH altering agents like chlorine or bromine.
If the alkalinity is in the proper range (80-120 parts per million), the pH will hold steady and pH bounce will be eliminated. However if the alkalinity is to high, the pH levels may drift up into higher levels, leading to scaling water conditions or make it to difficult to adjust the pH. To increase the Alkalinity use Baking Soda (sodium bicarbonate 100%).
Sodium bicarbonate is required to raise the alkalinity. Use small amount 1 to 3 TBS at a time for adjustment
To decrease the alkalinity using Muriatic Acid (HCl). Acid, Caution! (Only service tech should use this product)
Note Muriatic acid is used to both lower pH and Total Alkalinity. The technique of adding this acid determines which will To decrease the alkalinity using Dry Acid (Sodium Bisulfate 93.2% The spa needs to be turned off and wait 10 minutes before adding pour the required amount of Muriatic acid into the middle of the spa and leave for 10 minutes before powering back up spa.
REMEMBER: The spa must be allowed to rest for 6 to 8 hours before a accurate test can be made!