Balancing your pool water chemistry can be very difficult, which is why it is important to know what chemicals to use and what they do. Proper maintenance of your pool’s water chemistry ensures that the water is clean, safe, and comfortable. There are five main chemical levels that should be monitored and maintained. These chemicals are chlorine or bromine, stabilizer, pH, alkalinity, and hardness. These levels should be checked at least every week. Additionally, other chemicals like algaecide, stain and scale, and a clarifier are also good to have on hand.
Chlorine
Chlorine is one of the most common chemicals used to maintain a pool. It is a sanitizer which is used to kill germs, destroy algae, and prevent the growth of bacteria. Chlorine comes in several forms, including liquid, powder, and pucks. Liquid chlorine is usually the best option for quickly raising chlorine levels in your pool and is the fastest way to clear up your pool water. Chlorine pucks in a chlorinating system are also a great option for maintaining chlorine levels, as they can slowly add chlorine as they dissolve.
A saltwater pool also uses chlorine. Saltwater pools use a salt cell/generator to break down salt molecules and produce chlorine. A salt system provides a constant supply of chlorine into the pool. (Salt levels: 2700-3400 ppm)
Ideal Chlorine Levels: 1-3 ppm
Bromine
Bromine is another sanitizer that is often used as an alternative to chlorine. It works just as well as chlorine at keeping your pool water clean and safe to swim in. Unlike chlorine, bromine does not come in a liquid form and is only available in tablets, granules, and as a salt. It’s most commonly added to your pool water by dissolving tablets in a brominating system.
Ideal Bromine Levels: 3-5 ppm
Stabilizer
Stabilizer, also known as cyanuric acid or conditioner, is used to protect the chlorine in your pool from the sunlight destroying it. Without stabilizer, the chlorine will be deactivated quicker and you’ll have to add chlorine more often. Stabilizer can come as a liquid or granular powder and is often in chlorine pucks. If your stabilizer levels become too high, the only way to lower them is by replacing the water in your pool.
If your pool uses bromine instead of chlorine, then stabilizer is not needed.
Ideal Stabilizer Levels: 30-50 ppm
pH
pH measures how acidic or basic (alkaline) your pool water is. The pH scale is measured from 0 to 14, where anything below 7 is considered acidic, above 7 is basic, and 7 is considered neutral. High pH can cause cloudy water, scaling on pool surfaces, and eye and skin irritation. Low pH can cause stains, corrosion, and etched plaster. The pH levels of your pool can be adjusted up or down using pH Plus or pH Minus pool chemicals.
Ideal pH levels: 7.2-7.8
Alkalinity
Alkalinity levels measure the amount of alkaline materials in your pool water. Keeping the total alkalinity of your pool at ideal levels is important because it acts as a stabilizer for your pH levels. With low alkalinity levels, the pH of the water may fluctuate up and down and will be very difficult to control. With high alkalinity, your pH will go up and may be difficult to bring back down.
To increase alkalinity, ALKA Plus pool chemicals can be used, this will also raise pH a little. Another option to raise alkalinity is baking soda. To lower alkalinity, use sodium bisulphate (dry acid) or muriatic acid. If you have a concrete/plaster pool, either acid should not be used, the only option to lower is removing water.
Ideal Total Alkalinity levels: 80-120 ppm
Total Hardness
Total hardness measures the amount of calcium and magnesium carbonate in your pool water. With pool water, we focus only on the calcium in the water. For concrete/plaster pools it’s important that the total hardness is above a certain level to prevent etching. If the hardness of your water is too high it can cause stains and scaling on your pool surfaces.
Calcium chloride is a common pool chemical that can be used to increase total hardness. If the total hardness of your pool water is too high, then the only way to decrease it is to replace the water in your pool.
Ideal Total Hardness levels: 175-300 ppm (225-400 ppm for plaster)
Other Chemicals
Algaecide
Algaecide is used to prevent algae growth in your pool water. Unfortunately, algaecide is not a great solution to remove algae. The best way to prevent and kill algae growth is a sanitizer like chlorine or bromine.
Stain and Scale
A stain and scale treatment will help remove metals like iron from your pool water. If your water contains a lot of metal, you may notice yellow or brown stains around the pool. The stain and scale treatment works by making it easier for the filter to remove the metal particles. This chemical should be used if you notice any stains or if you know there’s a lot of metal in your water.
Clarifier
A pool clarifier is used to reduce cloudiness from your pool water. It does this by combining the smaller particles in the water into bigger ones that your filter can remove. A clarifier can be used every couple of weeks or after backwashing a sand filter.
Conclusion
Understanding the roles of the chemicals in your pool is essential for maintaining clean and safe pool water. To ensure that you can adjust your water’s chemistry when needed, you should always have certain pool chemicals on hand. I recommend having 20 litres of liquid chlorine, a bucket of ALKA Plus, pH Plus, and pH Minus, and bottles of algaecide, stain and scale remover, clarifier, and stabilizer. With knowledge of these common pool chemicals, it should be easy to maintain your pool all summer long.
