How much baking soda do you add to lower the pH level in an above ground pool?

You should not add baking soda to lower the pH level of your pool. While baking soda can help to increase the pH level, it is not effective at lowering it. Baking soda (sodium bicarbonate) is a base and will actually raise the pH level of your pool water instead. To lower the pH of your pool, you will need to add an acid-based pH reducer such as muriatic acid or sodium bisulfate.