Troubleshooting Low pH and High Alkalinity In Your Pool

If you’re a pool owner, you know the ups and downs you can face when balancing the pH or even phosphate levels of your water. Keeping your pH levels safe and to standard means that you don’t have to worry about chemical consumption, bacteria overgrowth and other pool headaches you might come across. 

If you’re dealing with low pH and high alkalinity in your pool water, you can nip this in the bud by tackling each problem separately.

Low pH is sometimes due to excessive rainfall and will require a pH plus solution or the help of a water aerator to ensure that your water stays circulated and balanced.  To address the high alkalinity, you can add muriatic acid to your pool to ensure safe levels for swimming. 

Learn all about pH, total alkalinity and how the two pair to create the perfect balance in your pool. We will discuss all the common problems concerning these two regular maintenance practices and how to troubleshoot in a pinch. 

What is pH?

When you maintain a pool, you’re probably familiar with the term and practice of testing the pH levels of your water. The pH is a term that means “potential of hydrogen”- a fitting phrase for measuring the safety of the water you regularly swim in. The ideal pH value for any pool is 7.2-7.8. 

The activity of the acids in water must be maintained to ensure the pH levels are on the proper scale. A value of 7-14 is the basic range on a pH level stick with 14 being a high value and 7 being the neutral, safe value.

If your water is on the acidic side, you’ll be looking at a pH value of 0-7. Anything under 7 is a weaker value and may be corrosive. Your equipment and metals are in danger of being corroded at this level and your pool may need further assistance for pH balance.

What Does Total Alkalinity Mean? 

Total alkalinity is a term you may have heard frequently regarding the keeping and care of your pool. In short, it measures the water’s ability to resist pH reduction. Total alkalinity means that your water is stable and you won’t have any reduced pH levels that need further assistance. 

Total alkalinity measures all alkaline substances in the pool water that attract and release Hydrogen ions.

The release of those ions means your pool water is resistant to pH changes. Achieving total alkalinity is always the goal- you want your pH levels to always remain balanced with no reductions that need further chemical addition. 

Common Problems with Pool pH and Total Alkalinity

Some of the more common household issues with chemical levels are high/low pH, high/low total alkalinity and a combination of the two.

You may also face times where you can’t get your pH levels to decrease or increase, affecting the integrity of your pool water. Here is the lowdown on some of these frequent problems. 

Your Pool pH is High 

High pH can be detrimental to the health of your pool water. If you notice that your pH is on the higher side, which is usually over 8, you will want to address the problem immediately to prevent any unwanted occurrences.

Some of the main problems associated with high pH are cloudy water, scale build-up, eye irritation and clogged filters.

It can also affect your chlorine negatively, meaning that the chlorine is no longer doing its job to effectively disinfect your water. A high pH level can be due to excessive chlorine or algae growth. 

To eradicate this issue, you can use muriatic acid or sodium bisulfate, both available at local pool supply stores. If you are unsure of the process, you can also reach out to a professional, however this is a simple fix. 

Your Pool pH is Low 

If you’ve tested your pool water and your pH strip shows a low level, you will want to steer clear of swimming. This means the water is very acidic. This will typically result in eye irritation, dry nasal passages and skin itching. Not to mention, this can cause corrosion in your pool as well. A low pH needs immediate attention before entering the water again. 

The most common cause of low pH is rainfall. Rainfall water is acidic and can cause the pH levels to significantly drop.

When this happens and your test results come back low, you will need to treat the water. This is usually a simple fix, requiring a chemical compound called pH plus, which increases the levels instantly. 

The Total Alkalinity is High

High alkalinity is an issue that needs to be taken care of right away. You may notice that this condition can turn your water cloudy. It is also known to weaken the effects of chlorine, scale your walls and floor and make it hard to adjust pH in general.

There are several causes for this problem and they include too much chlorine, use of borax and curing pool plaster.

Luckily, it can be an easy fix with the help of the solvent muriatic acid, which is most commonly used in this situation. For the proper amounts, read instructions or consult with a pool professional. 

The Total Alkalinity is Low 

Low alkalinity occurs for a number of reasons. It is not safe to swim in a pool with low alkalinity due to the fact it can cause skin irritation, water corrosion and more. Your pool’s surfaces are at risk of peeling, bacterial and algae growth and more. Regular testing can diagnose this problem, and luckily, you can fix it at home. 

Rainfall and pool backwash are the most common reasons for this issue. You can add an alkalinity increaser to help get back to a basic level.

Sodium bicarbonate is the most popular chemical used, however it will be dependent on all of the pool chemical levels to help you determine the best course of action. A pool professional can help you if you’re unsure where to start. 

The Total Alkalinity is Low, but the pH is High 

Now that we know low alkalinity can cause so many problems such as irritation, corrosion and more, we know that the issue has to be eradicated immediately to prevent further damage. Rainfall is most to blame for this problem and luckily you can add a compound such as sodium bicarbonate to fix it. 

High pH can also be addressed by using a pH reducer such as Sodium Bisulfate. If you have tried fixing these issues with the proper chemicals and nothing has helped, it may require the help of a professional pool technician. 

The Total Alkalinity is High, but the pH is Low 

High alkalinity most commonly turns your water cloudy, affecting the chlorine and how it rids all the bacteria in your pool. Without clean water, you run the risk of hurting your skin, eyes and nasal passages. High alkalinity can be reduced with a chemical solution such as muriatic acid.

To increase your pH, you’ll want to use a pH increaser. This can sometimes occur when rainfall or snow adds bacteria and particles to your pool water.

A low pH can be dangerous to swim in, so you’ll want to add an increaser at the first sign of low levels. You can also aerate the water by following a few simple steps at home, in conjunction with the use of muriatic acid.  If you are struggling to balance both, you may need to hire a technician for further assistance. 

The Pool pH Will Not Increase or Decrease

As you know, the pool pH is important to ensure safe water for swimming. If you have tried increasers and reducers and your pool pH is not returning to base level, this may require the help of a professional.

You may be using a product that is not allowing your pH to return to its normal, safe levels. A professional can help you to decipher the source of the problem and get you back up and running. 

Common Fixes for pH and Total Alkalinity

For many of these typical pool water issues, you can simply fix the problem at home with the proper chemicals and a little patience. Here are some tips for helping to increase or reduce pH levels, to ensure a safe swimming experience. 

Use pH Increaser or Reducer 

If you need to raise or lower your pH levels, you can use chemicals at home that help to do so. If you want to give it a try, you can follow these steps to get your pH balance back on track before having to call a professional: 

pH Reducer
  • Gather your dry chemicals, safety gloves, a plastic measuring cup and scale 
  • Stir with a wooden stick
  • Read the back of your container for measurements. This will go by the size of your pool so make sure you are using the correct amount. 
  • Add the amount directed.
  • Test the pH of your pool shortly after you’ve added to make sure that your pH has increased or decreased to a base level. 

Aerate the Water

If you need to raise the pH, you can aerate the water easily at home. You can install an aerator right at home with the right tools and some simple step by step instructions. The aerator keeps your water circulating, ensuring clean and balanced water. Here is how you can start the process: 

  • Choose the location for your aerator, making sure that it is in a good place to circulate your water and with no visible blockages
  • Prepare the area, making sure there is nothing in the way of installation
  • Grab your garden hose and connect an end to the aerator unit, securing it with strong tape or a handy clamp.
  • Make a hole in the side of your pool at the chosen location using a hand drill.
  • Connect and use as necessary 

If you do not have the tools needed, you can always contact a pool technician to help you install an ideal aerator for your pool. 

How Much Does it Cost to Fix pH or Alkalinity in Your Pool? 

If you want to try your hand at balancing out your pH levels, you can easily do so by following instructions and basing the amounts off of the size of your pool.

You can even visit a pool supply store for advice on how to approach the problem you’re facing and they can point you in the right direction of what chemicals will need to be purchased.

For a maintenance visit regarding chemicals in the pool, you are looking at an $80-120 fee just for coming out to assess. This will not include the cost of chemicals used but could prove to be worth the expense for new knowledge of future maintenance. 

Fun Fact: If you install a pool aerator, you should turn it on for approximately one hour per day to improve circulation and balance of your pH.


Overall, pools require a lot of regular maintenance to ensure that the water quality is safe for swimming. A low pH means that your chlorine’s effectiveness has been compromised, and raising it with pH increasers will help to solve that issue.

High alkalinity can also be resolved with a chemical compound to ensure that you don’t have skin or eye irritation.

While there are many causes and certainly many future occurrences you will have to face, many of these issues are manageable at home or with the help of a professional. 

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