How to Test Pool Chemistry

Maintaining the proper chemistry in your pool water is one of the most essential tasks you'll have as a pool owner. It's not only crucial for keeping your pool clean and healthy, but it's also vital that you always refer to the pool manufacturer's guide to ensure that your warranty isn't voided due to poor water balance.

Starting the pool maintenance right might seem overwhelming and confusing at first, especially when dealing with pool chemicals. However, once you understand the reasons behind it, you'll see that balancing pool water chemistry is actually quite simple, which involves regular treatment to maintain a proper balance. It's crucial to keep stable water chemistry, which can be achieved by regularly adding calculated doses of chemicals or by monitoring levels and adjusting accordingly. If the water is not balanced, it can become corrosive or cause stains and scale on the surface of your pool equipment.

Additionally, when people swim in the pool, they leave behind body oils, hair, dead skin, and shampoo, among other contaminants, which can turn your pool into an unsanitary environment. The only way to prevent this is by using sanitisers. Still, for them to work efficiently and effectively, other factors such as pH, alkalinity, and calcium hardness must also be balanced. (Credit: Swim University)

Pool Chemicals: The Key to a Clean Pool

A clean and inviting pool doesn't just happen by chance; it results from careful pool maintenance and regular testing of your pool chemistry. Properly balancing the chemical components of your pool water is essential to ensure the safety, comfort, and longevity of your pool equipment.

pH Level: The Foundation of Pool Chemistry

Recommended levels: 7.2 - 7.6

The pH Level is the most key factor in your pool chemistry. It measures how acidic or alkaline your water is.

• Low pH (Too Acidic): A low pH level can lead to eye irritation and equipment corrosion, which creates an uncomfortable swimming environment.
• High pH (Too Alkaline): A high pH level can result in scaling and calcium buildup, which affect water clarity and equipment performance.

To lower the pH, you can use either liquid or dry acid, depending on your preferences and the specific needs of your pool.

Alkalinity Level: pH's Silent Stabiliser

Recommended levels: 100-200ppm

Alkalinity, often overlooked but equally vital, refers to the amount of carbonates and hydroxides in your pool water. These compounds help regulate and moderate the pH level.

• Low Alkalinity: low alkalinity levels may go unnoticed, but they can lead to low pH levels, which results in corrosive, acidic water that can damage the surface of your pool equipment.

Alkalinity levels can be raised by adding sodium bicarbonate, which helps stabilise the water and maintain the pH balance.

Calcium Hardness: The Backbone of the Water

Recommended levels: 200-300ppm for concrete/tiled pools and 100-250ppm for vinyl and fibreglass pools

Calcium hardness is a measure of the calcium content in your pool water. It plays a pivotal role in water clarity and equipment longevity.

• High Calcium Hardness: Excess calcium in the water can make it cloudy and lead to calcification.
• Low Calcium Hardness: Low levels can make your water feel slimy and damage metal fittings, leading to staining.

Calcium hardness can be adjusted using calcium chloride, which helps maintain the right balance for your pool.

Free Chlorine: The Pool's Guardian

Recommended levels: 2-3ppm

Maintaining the appropriate free chlorine level is the most critical part of keeping your water in balance. Chlorine is crucial in disinfection by killing germs, bacteria, and algae. Neglecting this aspect can lead to algae growth and unsafe water conditions. Free chlorine is available in various forms, including liquid, granular, and tablet, allowing you to choose the one that best suits your pool and maintenance routine.

Cyanuric Acid Level: Protecting Your Chlorine

Recommended levels: 30-50ppm

Cyanuric acid, also known as chlorine stabiliser, safeguards your pool's chlorine from the sun's harmful UV rays. This prolongs the effectiveness of the chlorine and ensures long-lasting protection. Maintaining the recommended cyanuric acid level is essential for chlorine stability. If needed, cyanuric acid can be added to reach the ideal range.

A well-maintained pool with properly balanced chemistry is a joy to swim in and minimises pool maintenance costs. Regularly testing and adjusting the pH, alkalinity, calcium hardness, free chlorine, and cyanuric acid levels are essential steps to enjoy a crystal-clear pool all year round.