Just mention the words ‘water chemistry’ to any pool owner, and watch their eyes glaze over and become filled with dread. Yes, water chemistry is one of the most frustrating chores of owning a pool, but it doesn’t have to be an incredibly overwhelming task. There are really just a handful of chemicals that you need to monitor in your pool and if you understand why they’re there in the first place, it becomes much easier to know when your swimming pool chemistry is off balance, and what you have to do to fix it.
No pool can survive without chlorine. Chlorine will work to clean your water of algae and bacteria and too much of it can cause swimmer’s eyes to burn and sting, while too little can make skin itchy and prone to rashes. Bromine is another chemical that is sometimes used in place of chlorine because it doesn’t cause these side effects. However, bromine is also much more susceptible to damage from ultra-violet rays.
Because chlorine can be easily damaged by the sun’s rays, and because so many pools sit outside and are especially prone to these harmful effects, chlorine stabilizer can be added to the water. This will help protect the chlorine from the sun’s rays.
Many people have heard of pH levels, but don’t actually know what they are. These levels refer to the ratio of acidity to alkalinity in the water and these levels can be tested with test strips, which you can buy on their own or in a pool testing kit. Ideally, a pool’s pH level should be between 7.2 and 7.6. Ideally, the pH level should be 7.5. If the pH level is too low and needs to be raised, soda ash can be added. For pH levels that are too high, sodium bisulphate can help lower them.
Total alkalinity measures the total amount of alkali compounds that are in the pool water. This measurement is what’s responsible for the pH level fluctuating in the pool. The total alkalinity measurement in the pool should be anywhere from 80 to 100 parts per million. If the pH levels in your pool are too low, the chances are that the total alkalinity will also be too low. Likewise, if the pH levels are too high, the total alkalinity is most likely also going to be too high.
This is the last level you’ll need to measure in your pool’s water and it measures whether or not the water is too hard or too soft. Soft water doesn’t have enough calcium and will be very corrosive to the surfaces in the pool. Hard water on the other hand, has too much calcium in the water and when this happens, it can begin to scale and will start to form on ladders, steps, and other pool surfaces. Generally, a pool service technician will be able to best advice on how to return the calcium hardness level to normal.