Plan the perfect garden with our interactive tool →

Will Borax Bring the PH Level Down in My Pool?

Thinkstock/Comstock/Getty Images

Swimming pool owners love their pools for the fun they can bring. However, pool owners often find themselves confused about their pools' water chemistry. Swimming pools present a variety of issues related to pH, for example, that can seem daunting. However, gaining an understanding of pool water chemistry, including pH, can help a pool owner lessen her worries. And a pool owner that understands pool chemicals, such as borax, and how they're used to adjust pH will worry least of all.

Adjusting pH

A swimming pool's pH balance is vital to the clean and sanitary operation of any pool. The pH balance in a pool directly affects how effectively the pool's disinfectant will work, for one. For example, pool chlorine operates inefficiently if pH in a pool isn't between at least 7 and 8. Fortunately, adjusting a pool's pH to correct levels is straightforward and involves adjusting pH using a chemical like borax. Also, you use borax in a swimming pool to raise, not lower, pH.

Borax Benefits

Using a chemical like borax to raise a swimming pool's pH comes with certain benefits. Unlike soda ash (sodium bicarbonate), borax in a swimming pool will help make a pool slightly alkaline without greatly raising its total alkalinity, which is different from the alkaline or acid determination made by pH. Another benefit is that borax, or sodium tetraborate pentahydrate, is a good swimming pool pH buffer and is more stable than common pool soda ash.

Using Borax

After adding borax to a swimming pool expect the pool's pH to climb greatly because borax has a high pH itself. All you'll need to do, though, is to add muriatic acid to bring pH back down. And once a pool's pH is brought back down below about 7.8, borax will serve as an effective pH stabilizer. After adding borax to a swimming pool, you won't need to raise or lower its pH as often.


Borax itself can be found in various swimming pool supply store pool aids and algistats. Borax is also part of the brand name of an extremely common "laundry booster," and it's the same product as pool store borax. Always ensure, though, that there are no phosphates or chlorine additives in the borax you buy for your swimming pool needs. Muriatic acid to lower pool pH is found in home supply and swimming pool supply stores and should be used strictly according to direction.

Garden Guides