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It is that time of the year again. The weather is heating up, parties are beginning, and the summer school holidays are just around the corner. I know what you must be thinking – you better get your pool ready now!

Preparing and maintaining a safe pool environment take a little bit of knowledge and pool chemistry. You must ensure to use the correct kit to test your pool water and ensure it is perfectly balanced and safe to use. Here is a crash course on some of the most important things you need to know for optimal pool function and enjoyment.

pH Levels –  its a fine balance.

The pH level measures the chemistry of our pool water and how healthy it is. The levels are graded from 1 to 14. A neutral level is valued at 7, anything below is considered acidic, and any grade above is known to be alkaline or basic. Your pool water should be tested on a daily basis and ideally sit within the pH range of  7.2-7.8. The optimum level of pH is 7.4 which coincides with the same level of pH in the human eye. pH levels below this optimum level can sting the eyes when swimming as they become corrosive, whereas anything above pH level 8 means the water is heading into a scaling condition and may cause a skin rash or irritation due to thriving bacteria.

pH levels otherwise known as “power of hydorgens” in pool water can fluctuate due to many factors. Some of these include varying water temperatures, weather changes, rain, bathers, debris or addition of other chemicals. To balance the pH levels you can use either a pH increaser (base) or decreaser (acid). Once the chemicals are measured and carefully added to the pool water we recommend re-testing the water to make sure the pH is at a safe level.

Total Alkalinity – the water’s ability to resist change in pH.

Some people mistake this with pH. The truth is these are related, however not the same. Total alkalinity measures the concentration of alkaline matter dissolved in pool water. Alkaline products neutralise acid and help the water resist change in pH. Total alkalinity is measured in parts per million or ppm (concentration of alkali in the water) and not on a pH scale (how alkaline or acidic the water is).

Knowing the alkalinity and pH of our pool water helps to determine and create an environment for chlorine to be more effective, because chlorine is stronger at lower pH levels. To increase alkalinity we use substances such as carbonates, bicarbonates and hydroxides to name the most popular. Whereas to decrease it we can inject carbon dioxide or muriatic acid. As chlorine can vary in pH, the total alkalinity would need to be adjusted accordingly between the ideal range of 80-120ppm dependent on the type of chlorine you use.

Cynuric Acid – keeps your chlorine alive.

Cynuric Acid is also known as a pool water conditioner, chlorine stabiliser, or CYA for short. Chlorine is used to keep our pool healthy and free of harmful bacteria. Cynuric acid helps retain chlorine levels in outdoor pools and prevents chlorine loss when pool water is exposed to direct sunlight, keeping it sanitized for longer. Some chlorine pool products today will already have cynuric acid added to them as it preserves the longevity of the chlorine product in the pool.

For optimum pool water health it is important to strike the right balance between chlorine and cynuric acid. The ideal range for cynuric acid is 30-50ppm. If your pool water has too little or too much CYA, the chlorine will become inefficient in killing bacteria or prevent algae growth. The most effective way to reduce cynuric acid is to drain or dilute the pool water with fresh water bringing the levels back down to a healthy position. Keep in mind after rainfall your pool chemistry can change and should be tested again. Always read the instructions as this chemical is an acid and can cause damage to your pool or body if not used correctly.

Total Hardness – is about the calcium.

Otherwise known as calcium hardness, total hardness is a measure of how soft or hard your pool water is. The measure indicates how much calcium is dissolved in your pool water with the ideal range floating between 200-400ppm. The test should be done once a week or fortnight depending on your water quality and other external factors.

Water that is too hard and over 400ppm can create a cloudy effect which can become impossible to clear up. In turn, calcium sediment can build up and create problems in your plumbing infrastructure, or on the pool’s surface walls. On the opposite spectrum, where total hardness drops below 200ppm, soft water becomes corrosive and can damage internal pipework and dissolve concrete which can become an expensive repair lesson if not maintained correctly with the right chemical balance.

Please note the above information is just a guide to provide you with basic knowledge on chemicals used for pool water. We recommend you use a professional to assist in maintaining the safety of your pool and if you decide to use any chemicals yourself without seeking professional help, you do so at your own risk. We also recommend you to always wear protective gear and read the instructions and hazard labels carefully to avoid any harm to yourself, other pool users or damage your pool.

It takes a number of chemicals to keep your pool water healthy, safe and swimmable. We recommend you have a regular schedule to test and maintain your pool safety levels. Please contact us if you have any questions or concerns.