The Importance of Water Chemistry

Regularly testing the water in your pool is crucial in ensuring proper pool maintenance. By mastering the skill of testing pool water, you are taking proactive measures to always guarantee a safe and enjoyable swimming experience.

Keeping your swimming pool's water chemistry properly balanced is key to reducing corrosion and extending the lifespan of your pool covers, pool lining, and equipment.

Ensure the perfect balance of your water to avoid any potential issues. Failure to maintain this balance can lead to two undesirable outcomes: corrosiveness due to insufficient chemicals or the formation of scale due to an excess of chemicals.

Both have negative effects on your health, the functionality of your pool equipment, and the condition of your pool's surface.

Here are the standard water parameters that are typically recommended:


Swimming Pool pH scale chart
pH 7.2 - 7.6
This is the most important chemical factor in your pool.
*pH refers to how acidic or alkaline your water is.
*Low pH (too acidic) can burn your eyes and even corrode your equipment.
*High pH (too alkaline) can lead to scaling & calcium build up.



recommended alkalinity levels
Alkalinity Alkalinity refers to the amount of carbonates and hydroxides in your pool water. These components help to regulate the pH level of your pool
*Low alkalinity can lead to low pH, causing corrosive, acidic water, which not only affects your skin and eyes, but can lead to damage of your pool’s surface and equipment.
*Your Total Alkalinity is raised by adding Sodium Bicarbonate.
*Have your pool water checked regularly by qualified professionals, who can advise on quantities required based on the size of your pool.
Maintaining the required Free Chlorine level is the most important part of maintaining your pool water balance.
*Chlorine, which is available in granular, liquid or tablet form, kills germs, bacteria and algae, ensuring your pool is safe to swim in.
*Should your chlorine levels drop too low you run the risk of your pool turning green, especially if you have phosphates in your pool.
If the pool is outdoors, it is vital that stabiliser (also known as cyanurate and cyanuric acid) be added and maintained at 50ppm. This compound reduces chlorine destruction due to sunlight. If someone is complaining that their chlorinator is not making enough Chlorine, you will usually find that their stabiliser level is too low, hence UV light is destroying their Chlorine as soon as it enters the pool.
However, too much stabiliser will reduce the effectiveness of chlorine and can result in poor quality water so ensure stabiliser does not exceed 80ppm.
Phosphates are mostly organic matter that have the potential to feed and encourage algae growth in your swimming pool, as well as cloud your water. Algae needs sun, water, air, and a food source such as nitrates and phosphates to flourish. This is why a swimming pool can be the perfect environment for algae to bloom! High phosphate levels also use up chlorine quickly, making it even more difficult to kill the algae and keep your pool clean. You may even assume that your chlorinator is not producing enough chlorine, when in actual fact the chlorine it is producing is being consumed more rapidly than it can physically be produced. How do phosphates get into your pool? Your pool is in an open area exposed to sun, water from rain, air, dust, and food for algae that may be introduced in many ways. Phosphates are present in your landscaping and fertilizer materials, and can be introduced by wind and water run-off, by means of rain or your own garden watering efforts. The phosphates can be deposited from environmental debris that enter the pool in the form of leaves, dust and bird droppings. Ideally, you want zero phosphates in your water. In order to rid phosphates from your pool, you will need to use a chemical to remove them, such as a Lanthanum based product. Along with using a phosphate remover, you need to remove debris such as leaves, sticks, and bugs on a regular basis. Emptying out skimmer baskets on regularly will also get rid of the debris quicker. It will also improve the water circulation.
Calcium Hardness is the measure of the amount of Calcium present in your pool water.
*High Calcium hardness can make your water cloudy, and lead to calcium build up on your salt cell and pool surfaces. It may even result in Calcium flakes in your pool.
*There are products available to keep your Calcium in solution (liquid form), which can be added every 3 months to prevent the effects of high Calcium.
*Low Calcium hardness can result in your water feeling slimy, damage metal fittings and cause staining on pool surfaces.
*The above information is as a general guide only. Your water parameters may vary depending on your pool sanitation system and type of pool you have. Be sure to check with your local qualified pool store. It always pays to take a photo of your system to show your pool store so they can advise accurately.
Back to blog