How To Reduce Alkalinity in A Swimming Pool

Before you go ahead and reduce alkalinity in your swimming pool you must first know what Alkalinity is and how it affects your pool. I know I am sounding old and wise but you may not have to reduce the alkalinity and this can save you money and time. Alkalinity is the pH buffer, which means it controls the pH balance in your swimming pool. Without it your pH would fluctuate so much you would never be able to control it. So alkalinity is necessary in a swimming pool but you may not always need to lower it.

Your swimming pool’s alkalinity should be between 100ppm (parts per million) and 150ppm. With that said there is a lot of room for play here. So the only reason you would ever need to lower it is if your alkalinity was above 175ppm and your pH was sky high, if your pH is fine then the alkalinity will lower itself over time with rain or any other element. Everything affects the pH and the alkalinity. But like I said, if your alkalinity is very high and your pH is high then lowering the alkalinity will be necessary.

Some stores don’t sell what is called an “Alkalinity Decreaser” or “Alkalinity Lowerer” so in it’s place you can use Muriatic acid which is also used to clean filters and acid wash concrete inground pools. By adding 21 oz to 10,000 of water you will lower the alkalinity by 10ppm. When adding muriatic acid you need to remember that it’s an ACID, which means it will eat away at plastics and vinyl. When adding to a concrete inground pool make sure to keep it away from plastic skimmers, return lines or steps. And if you are adding muriatic acid to a vinyl liner pool, in either an inground or an above ground pool, you should dilute the acid with water first in a large bucket.

Note: Also make sure that when adding this chemical to your swimming pool that your pool is running and water is moving.