Pool Water With High Alkalinity: Easy & Effective Step-by-Step Guide to Lowering Alkalinity

If you have a high alkalinity problem, you should know that there are a lot of ways to lower it. In this article, we will tell you about some of the most common ways to lower your alkalinity. Read more here.

Keeping your pool alkalinity in balance will make an enormous difference in how much time you spend maintaining your pool.

In today’s article, you’re going to understand everything about high alkalinity in your pool water, what causes it, how to test the alkalinity level, how to lower it, and much more. 

What Is Pool Water Alkalinity?

pH value alkaline

Water alkalinity is one of the most important elements that will impact the chemistry of your pool water. Total alkalinity and pH are interrelated because they both work on your pool’s acid. With the correct alkalinity range, we recommend between 80 and 150 parts per million (ppm), total alkalinity will help to keep the pH level stable.

It isn’t easy to keep your pH level in the optimum range if your alkalinity level is too high. You’ll know your pH level is too high when your pool becomes murky, there is scale buildup in your pool walls, and your chlorine is not efficiently sanitizing your pool.

The process of getting water alkalinity in the normal range can take weeks, so unlike balancing other chemicals that you can normally do within a day, you have to be patient with this one.

Why is High Alkalinity Level in Pool Water Not Precisely Good?

An alkalinity level that is excessively high in a swimming pool can lead to issues such as an unbalanced pH level, which contributes to high calcium levels.

High calcium levels can cause scaling, murky water, and clogged filters. And let’s not mention itchy skin and bloodshot eyes for your swimmers!

What Causes High Alkalinity in Pool Water?

There are a few factors that contribute to pool waters’ high alkalinity levels. Once you have determined what is causing the problem, then you can begin resolving the issue. 

Two of the most common reasons alkalinity levels are high is either human error or too much pool chemicals. However, the geographical area and acid rain is also a huge factor for high alkalinity levels. Acid rain affects your pool’s pH level greatly. 

Another reason might be sweat and lotion. The reason for this is that sunscreen contains numerous chemicals, and when you apply it to your skin and subsequently sweat in the sun, these chemicals enter the pool and alter the pH levels. This is also true for soaps and body washes.

A third reason could be because of an increase in temperature in your place. For example, if the morning temperature is quite cold and then suddenly it gets much hotter through the day, there’s a huge chance the alkalinity levels in your pool increase quite a lot.

Lastly, your water source is another factor contributing to high alkalinity levels. Water companies must reveal their water testing results to consumers, so feel free to give a phone call to help you determine what chemicals you will regularly need to keep your pool water balance at all times.

How to Test the Alkalinity Level of Your Pool Water?

Pool Water Test Kit

If you’re quite unsure if the alkalinity level is the problem, then you should invest in a good pool testing kit. These kits are a good investment for pool owners, and you can purchase them in most home improvement stores. However, many pool owners warn against buying test trips due to their inaccuracy to measure pool alkalinity.

Suppose you already have a pool water testing kit, and for some reason, it doesn’t contain the reagents necessary to measure alkalinity levels. In that case, you can always buy some alkalinity test strips separately. But again, some test strips are not quite as accurate, so be sure to purchase a reliable one.

Once you’ve gotten your vial and reagent ready for testing, collect a sample of pool water at around 12 inches below the surface. Then drop the reagents slowly into the pool water sample and use the manufacturer’s instructions to determine your reading. 

The ideal TA level is between 80 and 120 parts per million (ppm).

How to Lower Alkalinity With Muriatic Acid?

There are a few chemicals pool owners use to lower their pool’s water’s high alkalinity level, but the most common chemical is muriatic acid.

To lower alkalinity levels in your swimming pool, all you have to do is follow these simple steps:

Step 1: Turn Off the Pool Pump

Turn off the pool pump and wait approximately an hour for the water to stop moving.

Step 2: Measure the pH Levels in Your Swimming Pool

If it is alkaline, you will need to lower your pH level by adding muriatic acid, which is a base.

You should aim to reduce your pH to a range of 7.0 to 7.2. If your water has a high pH level, make sure to invest in a swimming pool acid dispenser and follow the manufactures instructions to lower your water’s pH. 

Step 3: Add the Muriatic Acid Slowly and Carefully

Follow the manufacturer’s manuals on how to safely add muriatic acid to your pool. Make sure that you do not exceed the limit for concrete pools! This is very important!

Otherwise, you run the risk of breaking your concrete flooring. Concrete pools react strongly to acid because they are porous, so the acid can actually eat right through the concrete.

Step 4: Aerate Your Pool to Break up the Remaining Alkaline

You can do this by turning your pool pump back on to increase circulation. Water features or a fountain can also make good aeration. 

Step 5: Increase the pH Levels Back Ranges 7.4 to 7.6

Once the alkalinity level is in your desired range, you’ll have to increase the pH levels back to the ranges 7.4 to 7.6. pH levels ranging from 7.0 to 7.2 will increase the efficacy of free chlorine.

Then, you’ll likely need to add a pool stabilizer to increase cyanuric acid (CYA) levels.

Metal Pool Ladder in Murky Water

Frequently Asked Questions (FAQs)

  • Can you still swim in a pool with high alkalinity levels?

High alkalinity levels in pool water are not going to kill you. Still, it can make you feel miserable when the pool becomes a slimy mess that causes dry and irritated eyes, earaches, dry skin, and itchy scalp.

So, it’s best not to use it if you think your pool might have high alkalinity water levels. But if you really have to, you can wear goggles, use earplugs, and limit your time swimming.

Above everything else, get that alkalinity level of your pool where it is supposed to be as soon as possible. It is beneficial to your health as well as the longevity of your pool.

  • Is it possible to use baking soda to lower alkalinity?

Sodium bicarbonate or baking soda is also a pool chemical you can use to increase water alkalinity levels. Conversely, muriatic acid is the most effective chemical to lower alkalinity levels in your pool.


Low alkalinity is a more common problem than high alkalinity levels, but both may cause an imbalance in your pool chemistry.

Having any one-off level chemicals can alter your pool’s chemistry and cause severe issues for the pool and your swimmers, so it’s always best to use an accurate testing kit so that you’ll be able to check on your pool water levels at least once a week. 

Bear in mind that lowering the alkalinity levels of your pool water may take longer than balancing the other levels. So you just be patient and keep testing!

Once your water reaches the ideal levels, make every effort to maintain it. You’ll thank yourself in the long term because your pool maintenance will be a lot simpler! 

Here are some related pool articles that will help with your pool maintenance:

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About the author

Brian Anderson

The rather dry pool world out there is in need of some passion to make it shine. With the help of my son Ruben and his wife Maria our mission is to help you create the favorite spot of your house - your pool.

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