Video: The Complete Guide to Swimming Pool pH

In the first in our water balance series, we offer a brand-new video talking about everything you need to know about your swimming pool's pH. If you'd rather read through the article though, it is available below the video as well. 

Understanding the pH Scale

The pH scale measures how acidic or basic a substance is, ranging from 0 to 14. A pH value of 7 is considered neutral, while values below 7 indicate acidity and values above 7 indicate a more basic (or alkaline) environment. Know this scale and maintaining the proper pH balance in a swimming pool in light of this scale is essential for water quality, swimmer comfort, and the effectiveness of pool chemicals.

Acceptable Ranges for Swimming Pool pH

Swimming pool water should have a pH level between7.2 and 7.8. This range ensures the water remains safe for swimmers while allowing chlorine and other sanitizers to function effectively. Water outside of this range can lead to various issues, including skin irritation, equipment damage, and compromised sanitation.

If your swimming pool's pH is out of this range, Pool Training Academy recommends you close the pool and adjust the pH until it is within these ranges again. 

Ideal pH Range for Swimming Pools

Although the acceptable range is 7.2 to 7.8, theideal pH range is 7.4 to 7.6. This narrower range optimizes chlorine efficiency while ensuring comfort for swimmers. It's also important to note that a pH of 7.5 closely matches the natural pH of human tears, reducing eye irritation and making swimming more enjoyable.

Problems Caused by Low and High pH

There are a number of issues that can come from a pH level in your swimming pool that is out of balance:

Low pH (Below 7.2)

• Increased corrosion: Acidic water can corrode pool equipment, ladders, and pipes.

• Eye and skin irritation: Swimmers may experience stinging eyes and dry, itchy skin.

• Decreased chlorine effectiveness: Chlorine dissipates more quickly, leading to inadequate sanitation and potential bacterial growth.

• Damage to pool surfaces: Plaster, grout, and vinyl liners can deteriorate faster.

High pH (Above 7.8)

• Reduced chlorine efficiency: Alkaline water reduces chlorine's ability to kill bacteria and algae.

• Cloudy water: High pH can cause calcium and other minerals to precipitate, leading to murky water.

• Scale buildup: Excessive pH encourages the formation of scale on pool walls, plumbing, and filtration systems.

• Skin and eye irritation: High pH levels can cause discomfort for swimmers, similar to low pH levels.

How to Adjust pH Levels

Adjusting your pH when it is out of balance is critical in keeping swimmers healthy, and your pool's environment safe for your surfaces as well as your equipment. 

Raising pH

If the pH is too low, you can raise it by adding:

• Sodium carbonate (soda ash): The most common way to increase pH levels in a pool.

• Sodium Hydroxide:This is a liquid pH increaser that is used for automated dosing systems mainly

• Oxygen:You can inject oxygen into your water to raise your pH as well. 

Lowering pH

If the pH in your swimming pool is too high, you can lower it by adding:

• Muriatic acid: A strong acid that quickly reduces pH and alkalinity.

• Sodium bisulfate (dry acid): A granular alternative to muriatic acid, often used in residential pools.

Does  Lowering pH Also Affect Alkalinity?

If using muriatic acid or sodium bisulfate to lower your pH, it will indeed affect your alkalinity levels in the pol as well. If those alkalinity levels are affected, simply raise them back up to acceptable ranges and you will get the best out of your pH once again. 

How Do I Learn More About My Swimming Pool?

Knowing about the in's and outs of your swimming pool pH is only one of the many challenges pool and spa operators as well as homeowners face on a day to day basis. This article has given you a good, but brief understanding of a single aspect of professional swimming pool operation. Thankfully Pool Training Academy offers Certified Pool Operator® (CPO) Certification courses that will help you become the best aquatics operator you can be. To get signed up for a CPO Certification in your area, please follow this link: Click Here