How to Add Baking Soda to Your Pool: A Step-by-Step Guide

Before you begin, you’ll need to know what kind of water you’re working with. Follow the directions on your pool test strip to see the current levels of your pool. 

Your pool should be somewhere between 110 and 150 parts per million for alkalinity and have a pH between 7 and 7.6. Anything higher than 7 is called basic (like bleach or drain cleaner) and anything lower is called acidic (like battery acid or orange juice). The goal is to land in that sweet middle spot.

The next two steps are the hardest parts of this whole DIY: math. Before you can start adding baking soda to your pool, you need to know your pool’s total volume of water. The math is relatively simple, but it may have been a while since you’ve done this type of calculation. 

Here are the formulas for both a rectangle and a round pool:

• Rectangular pool: Length x width x water depth x 7.5 = volume in gallons

• Round pool: Diameter x water depth x 7.5 = volume in gallons

If your pool isn’t the same depth all the way across, use your average depth from the water line to the pool floor for the calculations. To do this, add together the deep end and the shallow end, then divide by two. So if your deep end is 7 feet deep and the shallow end is 3, the average depth would be 5. 

We multiply by 7.5 because that’s how many gallons of water there are in each cubic foot.

To raise the alkalinity by 10 ppm, you’ll need 1.5 lbs of baking soda per 10,000 gallons of water. So taking your number from the calculation above, you’ll do another math equation. 

So if you need to raise it by 30 ppm because it’s at 80 ppm per your test strip, and your pool is 10,000 gallons, you’ll need 4.5 lbs of baking soda. You can use an online calculator to do this math quickly for you.

Back to the easy part. After you know how much baking soda you need, it’s time to pour it in. Work your way around the pool, dumping a little bit of the baking soda as you go. Once it’s all poured in across the pool, turn on the pool’s jet system to help it circulate efficiently.

Wait at least six hours before you test the pool again (and ideally 24 hours) to give the baking soda enough time to fully dissolve.

As one final check, test your pH balance again. If it’s below the recommended amount, repeat the steps above. 

If it’s above the recommended amount, you have a few options. You can either add more water and chemicals to dilute the baking soda more, wait another 24 hours to see if it naturally lowers, or use muriatic acid to lower the alkalinity. If you choose muriatic acid, your pH will lower too, so you can either add more water (which will require more chemicals because they’ll be diluted), wait for the alkalinity to naturally lower, or use a chemical like muriatic acid to lower it. 

If you use muriatic acid, your pH will lower as well, so you’ll need to raise the pH levels in your pool accordingly.