Maintenance & Care

Pool chemistry & water testing

Diving into a sparkling clean pool on a hot summer day is a luxury we all enjoy. But have you ever wondered what it takes to maintain that crystal-clear water? Proper pool water testing and maintenance is essential for a safe and enjoyable swimming experience.
Pool chemistry and water testing.

Short Summary

  • Regular testing and balancing pool water is essential for a healthy swimming environment.
  • Monitor key parameters such as pH, alkalinity, calcium hardness & sanitiser levels to maintain optimal chemistry.
  • Adjusting the water chemistry and using clarifiers/sequestrants can help prevent & treat common pool issues.

The essentials of pool water testing

As a pool owner, you understand that pool water testing is a crucial aspect of maintaining a healthy and safe swimming environment. Inadequate pool maintenance can lead to unbalanced water chemistry, causing corrosion of pool equipment, scaling, and even health issues for swimmers.

Regular testing ensures that your pool chemicals are at their optimal levels, safeguarding your swimming pool surface, equipment, and swimmers' wellbeing. Let's dive deeper into the importance of testing your own pool chemical and water and how often you should do it.

Why test your pool water?

Pool water testing is vital for sustaining a healthy and secure swimming environment, preventing issues like cloudy pool water, and enabling the efficient use of pool chemicals. By testing and balancing your pool water regularly, you ensure the effectiveness of disinfection, water quality, and the longevity of your pool surfaces and equipment.

This not only keeps swimmers safe and comfortable, but also protects your investment.

How often should you test?

To maintain a balanced swimming pool, it is recommended to test your pool water at least once a week. External factors such as rainfall, extensive pool usage, and temperature fluctuations can impact your pool water chemistry, making regular testing crucial.

By staying on top of your pool water testing, you'll ensure a clean and safe swimming environment for everyone.

Pool water testing methods

When it comes to testing pool water, there are three primary methods available: test strips, liquid test kits, and professional pool testing services. Each method has its advantages and disadvantages, which we will discuss in the following sections.

Choosing the right testing method for your needs is crucial for keeping your pool water chemistry balanced and well-maintained.

Test strips

Test strips are a popular choice among pool owners due to their quick and easy use, affordability, and relatively accurate results. By simply dipping the test strip into your pool water and comparing it to the provided color chart, you can detect key parameters such as pH, total alkalinity, calcium hardness, and sanitizer levels.

Test strips, however, may not be as accurate as other testing methods, but they are suitable for routine checks and on-site spot testing.

Liquid test kits

Liquid test kits offer a more accurate and precise analysis of your pool water chemistry, using dropper bottle reagents to test the water. Although they may be slightly more time-consuming and expensive than test strips, liquid test kits provide a higher level of accuracy and a broader range of chemical measurements.

This allows for better-informed decisions when it comes to balancing your pool water and maintaining the desired water quality.

Professional pool testing services

For the most accurate and comprehensive pool water analysis, consider taking a water sample to a professional pool testing service. These experts will provide precise results, identify and address potential issues, and ensure a safe and healthy swimming environment for you and your loved ones.

Although this method may be more expensive than test strips or liquid test kits, the peace of mind it provides may justify the added expense. Additionally, some pool shops do this testing for free, so it's worth calling around.

Key parameters to monitor

To achieve optimal pool water chemistry, it is essential to monitor four key parameters: pH levels, alkalinity, calcium hardness, and sanitizer levels. Maintaining these parameters within their recommended ranges will help you keep your pool water clean, safe, and comfortable for swimmers while also protecting your pool equipment from damage.

Let's delve into each of these parameters and the importance of monitoring them.

pH levels

The pH level of your pool water is a measure of its acidity or alkalinity, with a recommended range of 7.4 to 7.6. An overly acidic or low pH amount can irritate the eyes and corrode pool equipment, while an overly alkaline pH can lead to scaling and calcium buildup.

Factors such as rain, debris, and pool usage can influence pH levels, making it essential to test and adjust them regularly using pH increasers or decreasers.

Total alkalinity

Total alkalinity is a measure of the alkaline substances present in your pool water, playing a crucial role in maintaining pH levels. A balanced alkalinity level (typically between 80-140 ppm) acts as a buffer, preventing sudden shifts in pH levels and maintaining a stable pool water environment.

To adjust alkalinity, you can use alkalinity increasers or decreasers, depending on whether your pool's alkalinity is too high or too low.

Calcium hardness

Calcium hardness is a measure of the amount of calcium present in your pool water, which is essential for protecting pool surfaces and equipment from corrosion and scaling. The recommended level for calcium hardness for concrete pools is 300ppm.

To manage calcium hardness, you can add calcium hardness increasers if levels are too low or use a sequestering agent to lower levels if they are too high.

Sanitizer levels

Sanitizing your pool water is vital for killing bacteria, viruses, and other contaminants in chlorine pools that can cause illness and discomfort to swimmers. The recommended sanitizer levels for pool water are 3 ppm for chlorine, 3-5 ppm for bromine, and 30-50 ppm for biguanide.

Regular testing and adjusting sanitizer levels will ensure a clean and healthy swimming environment, protecting both swimmers and pool equipment from harm.

Adjusting pool water chemistry

Now that you understand the key parameters to monitor, it's time to learn how to adjust your pool water chemistry to maintain optimal levels. This involves balancing pH, adjusting alkalinity, managing calcium hardness, and optimising sanitiser levels.

Balancing pH

To balance the pH in your pool, you'll need to use pH increasers or decreasers, depending on whether your pH level is too low or too high. If both pH and alkalinity levels are low, it's recommended to adjust alkalinity first.

Regular testing and adjusting pH levels will not only help maintain a comfortable swimming environment, but also ensure the effectiveness of sanitizers and protect pool equipment from damage.

Adjusting alkalinity

To increase alkalinity in your pool, you can add an alkalinity increaser, such as 150 grams of ph buffer per 10,000 litres of pool water.

Maintaining proper alkalinity levels will stabilise pH levels and prevent drastic fluctuations, ensuring a balanced and comfortable pool environment for swimmers.

Managing calcium hardness

Managing calcium hardness involves adjusting the calcium levels in your pool water to prevent corrosion and scaling, which can damage pool surfaces and equipment. If ideal calcium hardness level is too low, you can add calcium hardness increasers to raise the levels.

Conversely, if calcium hardness is too high, you can use a sequestering agent to lower the levels or partially drain the pool and replace the water.

Optimizing sanitizer levels

Optimizing sanitizer levels in your pool involves maintaining the correct concentration of chlorine, bromine, or biguanide to effectively kill bacteria, viruses, and other contaminants. Regular testing and adjusting sanitizer levels will ensure a clean and healthy swimming environment, protecting swimmers from illness and pool equipment from damage.

Preventing and treating common pool problems

Armed with the knowledge of how to monitor and adjust your pool water chemistry, you can now prevent and treat common pool problems such as algae growth, cloudy water, and staining.

In this section, we'll discuss how to control algae, use clarifiers and flocculants to clear up cloudy water, and employ metal sequestrants to prevent staining.

Algae control

Algae control is essential for maintaining a clean and safe pool. To prevent algae growth in swimming pools, ensure that your chlorine levels are adequate and consider using an algaecide as a proactive measure.

If your pool is already experiencing algae growth, you can treat it using chlorine, algaecide, and other pool chemicals to kill the algae and restore water clarity.

Clarifiers and flocculants

Clarifiers and flocculants are pool chemicals that help clear up cloudy pool water by aggregating and settling small particles for more effective filtration and removal. Clarifiers work by causing the small particles to clump together, allowing the pool filter to capture them more easily.

Flocculants, on the other hand, cause the particles to settle at the bottom of the the pool floor, where they can be removed through vacuuming.

Metal sequestrants

Metal sequestrants are pool chemicals that bind to metal particles in pool water, preventing them from attaching to your pool walls and surfaces and causing staining. By using metal sequestrants, you can maintain the clarity of your pool water and protect your pool surfaces from unsightly stains.

It is important to choose a high-quality metal sequestrant, such as one derived from phosphoric acid, for optimal performance.

Advanced pool water testing options

For pool owners seeking more accurate and precise pool water testing, advanced testing options such as digital water testers and specialty tests are available. These advanced options can provide greater insight into your pool water chemistry, allowing you to make more informed decisions when it comes to maintaining your pool's water quality.

Digital water testers

Digital water testers are sophisticated devices that measure the chemical levels in pool water, providing a more accurate and reliable reading than traditional test strips or liquid test kits. By using a digital water tester, you can gain a better understanding of your pool water chemistry and make adjustments as needed to maintain optimal water quality.

These devices are easy to use ahd provide quick results, allowing you to quickly identify any issues with your pool water and take the necessary steps to correct them. With a digital water tester, you can ensure that your pool is safe and enjoyable.

Specialty tests

Specialty tests, such as those for total dissolved solids, cyanuric acid, phosphate, and iron, can provide valuable insights into specific aspects of your pool water chemistry. By utilizing these specialty tests, you can more accurately diagnose and address potential issues in your pool water, helping to maintain a clean and safe swimming environment.


In conclusion, maintaining optimal pool water chemistry is essential for a clean, safe, and enjoyable swimming experience. By understanding the importance of basic pool chemistry and water testing, learning the different testing methods, monitoring key parameters, and adjusting your pool water chemistry as needed, you can prevent common pool problems and ensure a healthy swimming environment. So grab your test kit, dive into pool water testing, and enjoy the crystal clear waters of your well-maintained pool!

Frequently asked questions

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How often should you clean your pool?
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For optimal pool health, it's important to clean your pool regularly. We suggest doing a full clean at least once a week, including brushing the walls and vacuuming the floor to remove dirt and debris. Skim the water's surface and brush the walls and pool floor to remove leaves and other items.

Additionally, if you see algae form, take immediate action to rectify the problem.

What is the best way to test pool water?
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The best way to test pool water is to use a reliable pool test kit. This will enable you to check the chlorine, pH, alkalinity and other important parameters in your pool, as well as compare it with the ideal range, ensuring your pool remains safe for swimming.

Doing regular tests is highly recommended for anyone wishing to keep their pool clean and healthy.

Where can I get my pool water tested by a professional?
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Most people choose to get their pool water tested at their local pool shop. You can also get your water tested at Bunnings who offer a free service. In both instances, you should get fast, accurate results and information on the right chemicals in the right quantity to get your pool in the best condition.

Just be aware that the quality of the recommendations and advice you receive can vary a lot. We recommend that you invest some time in finding a highly skilled pool chemistry expert to ensure you're getting good advice. This is also likely to cut down on the amount of unnecessary chemicals you use.

What is proper pool chemistry?
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Maintaining the proper balance of pH, Total Alkalinity, Calcium Hardness and Chlorine levels is key to having a safe and healthy pool. The ideal range for these parameters is: pH 7.4-7.6, Total Alkalinity 80-140 ppm, Calcium Hardness 250-350 ppm, Cyanuric Acid (Stabiliser) 30-50 ppm, and Chlorine levels 1-3 ppm.

Having these levels in check will ensure your pool is properly sanitised and enjoyable for all.

How often do you add chlorine to pool?
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In order to keep your pool water safe and clean, it's important to add chlorine on a regular basis. For most pools, a tablet should be added every 3-7 days, depending on the results of water tests.

This will ensure that your swimming area is properly sanitised and protected.

What is the best way to keep a swimming pool clean?
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The best way to keep a swimming pool clean is to create a regular weekly pool maintenance schedule, which includes skimming leaves and debris, brushing the walls, vacuuming, cleaning the skimmer, running the pump, backwashing filters as needed, and testing and adding chemicals to the water.

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