Reducing Pool pH

For a new pool owner, managing pool chemistry can be intimidating. While automatic chemical feeding systems or erosion systems tend to function well, they are not without their problems. Changes in the weather, the amount of sunlight, temperature, etc., can all affect the chemical balance of your pool water. Having improper levels of chemicals in your pool can render it unsafe, and even lead to damage to the pool itself if not corrected.

One of the most common water issues for pool owners is pH. Regular water tests will alert you to potential problems. This is why it is so important not to skip those water tests – the sooner you can catch the problem, the easier it is to fix it. But even still, issues with chemical balances will occur and it can take time and a bit of understanding to know what to do to get your levels back where they need to be.

Water that has too high of a pH level leads to a range of different problems. It can render the chlorine in your water ineffective, meaning that the water is not properly sanitized and thus unsafe to swim in. You might notice that your system is using a lot more chlorine than it would normally use. This is the system’s attempt to keep pace with the lack of active chlorine in the water. Untreated, a high pH can lead to clogging in the pipes and filters, which reduces flow and circulation, exacerbating the problems.

A high pH also has negative effects on people who swim in it. It can lead to eye and skin irritation.

What is pH and Why Is It Important?

The pH of a pool is simply a measure of the total alkalinity of the water. This measure will tell you whether the water in your pool is acidic or basic. The desired pH range for a pool is between 7.2-7.6. Getting out of these ranges on either end can lead to issues with pool functioning and water safety. 7 is neutral. The lower your pH, the more acidic the water will be, whereas the higher the pH, the more basic it is.

While most pools do a fairly good job of keeping these levels in balance, they are not perfect and ever-changing outdoor conditions can make it difficult for the system to keep pace with the needs of the water. Having acidic water can lead to corrosion and dissolving of plaster or other lining materials that will lead to pockmarks on the bottom or sides of the pool. Water that is too basic can lead to scaling in the plumbing, as well as cloudy water.

If you find that your pH levels are out of whack, it is important to get them back into the appropriate levels. This helps to ensure that you do not unnecessarily damage any of your equipment and that you keep the water safe for your friends and family. Several factors can lead to the pH getting out of balance, as well as a few ways to address the problem.

Why is Your pH High?

Most commonly, people will have pH levels that are too high, rather than too low. It is not uncommon to have errant spikes or dips in your pH level, and often the automatic chemical feeding system can manage these spikes and quickly get them back in range. However, sometimes the problem has gotten too far out of control for the system to get back in balance. Or, perhaps, you notice that you are regularly having a problem with pH levels that are too high.

Unfortunately, pH is one of the most difficult chemicals to keep in balance. pH is sensitive to changes in the amount of sunlight, as well as the outdoor temperature. These variations can reduce or increase the effectiveness of the acid you use to balance the pH. When your pH is too high, it neutralizes the chlorine, rendering it useless when it comes to water sanitation.

While many factors can lead to spikes in pH, the most common are:

  • Improper Chemical Usage – Most experts recommend that you use discretion when adding chemicals to your pool. You can always add more, but you can’t easily remove what you have added to the water. Many products are designed to help reduce the pH level, and adding too much can lead to more difficulty in getting the levels back in balance.
  • Shocking the Pool – Regularly shocking your pool helps to keep the water sanitized and safe to swim in. There are, however, a variety of different types of pool shock you can use. Certain types, such as calcium hypochlorite, can lead to a pH spike. This doesn’t mean you shouldn’t use this type of shock, but it underlines the importance of doing regular water tests.
  • High Levels of Alkalinity – The pH level of the water will almost always be out of balance if your water is highly alkaline. Alkalinity and pH are intimately connected and will play off one another.

How to Reduce the pH Level

Two main products can be used to reduce the pH level of your pool water. These are sodium bisulfate and muriatic acid. Some products have names like “pH reducer” which will contain one of these substances. Either one of these chemicals works well to reduce pH, but it is important to note that these are very strong chemicals that can cause skin irritation and even damage pool surfaces, so extreme caution should be exercised when using these products.

Sodium bisulfate

This is a powdered form of acid and is commonly used by professional pool technicians as a pH reducer. It is still a powerful chemical, but it is not nearly as dangerous to work with as muriatic acid. As it comes in powder form, it is recommended to check the weather conditions to not try to use it on a windy day.

When using sodium bisulfate, you want to first check your chemical levels with a water test. Follow the product’s instructions as to how much to use – it is easy to overdo it, which can itself lead to further problems. You put the powder into the site of the return jets to be distributed throughout the water. It should be noted that large bodies of water like pools take time to absorb all the chemical and for it to start doing its job. Waiting about 24-hours and then doing regular water tests will let you know if this was successful.

Muriatic Acid

This chemical is also often known as hydrochloric acid. This comes in a liquid form and has a variety of other uses besides reducing pH. It is often one of the chemicals used in automatic feeder systems and it is also the chemical used to clean pool surfaces, which is known as an acid wash. Extreme caution should be taken when using this product. You follow the same process for reducing pH using muriatic acid as you do sodium bisulfate.