How to Lower Alkalinity in Pools

Whether you own your own pool or frequent the neighborhood spot lowering the alkalinity of a pool isn’t too difficult. Maintaining a swimming pool is all about keeping proper balance among multiple different levels. Alkalinity is one of these factors that can lead to spending on pool maintenance and other issues if neglected.

Even though high alkalinity isn’t quite as dangerous to your equipment as low alkalinity maintaining a proper balance is key. This article will explain the ins and outs of reducing alkalinity in pools. Why it’s necessary, how to do it, and all you need to know to enjoy your pool in alkaline harmony.

The Threat of Pool Alkalinity

The Threat of Pool AlkalinityBalance is the most important factor for jumping in your pool and coming out relaxed instead of a burning, itching mess with multiple regrets.

Possibly the biggest issue with high alkalinity is the amount of scale that can start to build up. Just like with fish it may add texture but it isn’t something you want to deal with. Heavy scaling can lead to maintenance issues as things fail to function properly.

You might also find your pool water to be pretty cloudy if your alkalinity is too high. Another issue that might pop up is a higher water pressure reading than you’d expect even after backwashing. While low alkalinity might be more detrimental in the long run maintaining balance is the only way to truly enjoy your pool experience.

Beyond its effect on the overall lifespan of your pool lowering alkalinity can also benefit how it feels to swim in it as well. The biggest issue for swimmers with high alkalinity pools is how they can cause skin irritation or make your eyes burn. You might also suffer from a sticky skin and hair feeling that is also uncomfortable.

Finally, a high alkalinity pool makes it difficult to adjust your pool’s pH. Another one of the three necessary adjustments for keeping your pool balanced fixing on can help you fix the other as well. Adjusting your alkalinity will make it easier to adjust pH unless it is far below 7.0. You want at least a pH of 7.0 before you start altering the alkalinity.

How Does My Alkalinity Get So High?

Often user error is a reason behind alkalinity though it is an issue that can evolve over time. Adding too much sodium bicarbonate also known as baking soda is a common mistake. The fact that you need to stop your pool from pumping and wait multiple hours between testing makes the process time-consuming. For this reason, many users will adjust their pools in small increments until they get used to their pool. This is also because the local water source can have an effect on your pool’s alkalinity.

Many municipal water sources favor a higher alkaline solution in their water to prevent corrosion in pipes and sewer lines. You can contact your local water company to find out details on water quality levels that might ease the process. Alkalinity is just something that will rise on its own over time from swimming, evaporating, backwashing, and more.

Methods for Lowering Swimming Pool Alkalinity

There are two main methods for lowering alkalinity in pool water but they are relatively similar. The main difference will be in how you handle the chemicals. Though each chemical alters your water quality differently so make sure you follow any help on the packaging. The perfect balance for alkalinity is generally between 80 and 120 ppm (parts per million).

Your two main options for lowering are sodium bisulfate and muriatic acid. Sodium bisulfate will require mixing until it dissolves. Muriatic acid will require more attention to safety with gloves, goggles, and long sleeves recommended

Alkalinity Lowering Process

The process is pretty much the same regardless of chemical used, just of course amounts will vary.

1Test the pool’s initial total alkalinity level. This is important as the basis for your adjustments
2Turn your swimming pools pump off. Waiting an hour for circulation to stop is necessary before you get started.
3Study your product. Your product should give you all the information you need to calculate how much is needed to get to that 100 ppm perfection.
4Add chemicals to pool water. After you have diluted your sodium bisulfate or measures your muriatic acid all you need to do is add them. Alway add them to the deep end of the pool. You also want to attempt to keep the stream as narrow as possible in order to get the most penetration while disturbing the pH the least.
5Let the pool sit for at least an hour. After that, you can turn the pump back on.
6Test the water. After six hours you should test your water to see if your mission was successful. Don’t wait too long. If you wait over 24 hours to test the water you might as well start over.
7Repeat the process. You won’t get it right every time so you might need to repeat the process until you do. Wait at least 2 or 3 days before adding more chemicals as the total alkalinity may still change.


If you can’t properly maintain the alkalinity of your pool you won’t be able to enjoy it for long. Balancing alkalinity is one of the three main factors in keeping a pool running properly. While others may have more of a direct effect on personal health alkalinity can seriously affect the health of your pool.

Knowing how to test your pool alkalinity will be a crucial part of not spending way too much extra money. Once you master how your pool’s size, local water quality, and adjustment in chemical amounts work, you’ll be able to easily enjoy your pool almost any time of the year.


Does muriatic acid lower alkalinity in pools?

Yes, muriatic does lower alkalinity in pools. As discussed above it is one of the two main substances used for lowering alkalinity in pools. Some customers prefer it over sodium bisulfate because it doesn’t need to be dissolved.

On the other hand, muriatic acid is a more dangerous chemical that’ll require more attention to safety. You don’t want to use muriatic acid without goggles, rubber gloves, and a long-sleeved shirt. Exposure of muriatic acid to the skin can cause burning along with exposure to eyes. Sodium bisulfate, muriatic acid, and even sulfuric acid affect the alkalinity and pH at different levels so make sure you read all the package instructions.

Are there any natural ways to lower alkalinity in pools?

Sorry, you won’t be able to lower the alkalinity of your pool without using some kind of chemical. Sodium bisulfate is basically baking powder so that is probably the most natural option. You will also find different water sources providing water with varying alkalinity levels. Allowing time and nature to take care of your pool is the absolute worst way to go if you wish to safely use it. The necessity to keep pools clean regardless of most situations just requires chemicals for any reasonable efficiency.

How to lower alkalinity in the pool without affecting ph?

It would be nice if this was possible but it is only a common folktale for wishful pool owners. There simply isn’t a way to affect one without affecting the other thanks to the nature of their chemical reactions. Using small amounts of chemicals is a good way to alter the balance slightly but it won’t stop the changes from happening. If you are attempting to lower the pH by adding acid the total alkalinity will also be lowered. On the other hand, if you use carbon dioxide to lower the pH the total alkalinity will be raised. Knowing how different chemicals interact with the balance of your pool is important to mastering maintenance.