What is total alkalinity?

Total alkalinity refers to the total amount of alkaline substances in the water. Alkaline substances include carbonate and bicarbonate which are present in pH increaser and pH buffer respectively. They do sound like the same thing but they are different. As the name suggests, pH increaser increases the pH levels, whereas pH buffer will increase alkalinity.  

Why do I need to balance alkalinity?

Alkalinity acts as a buffer for pH. When alkalinity is balanced it helps to prevent drastic changes in pH levels. Low alkalinity readings will increase pH sensitivity, meaning your pH can go from high to low and back very quickly. Having a low alkalinity can damage your pools surface, tile grout and equipment and can even leave us with itchy skin and burning eyes. On the opposite end of the scale, high alkalinity can decrease pH sensitivity, so your pH stays high and reduces chlorine efficiency. Having a high alkalinity reading can make your pool cloudy or even green if your chlorine is not being used to its capacity. Like low alkalinity, high alkalinity can leave us with burning eyes and itchy skin.  

How do I balance alkalinity?

Most of the time your alkalinity readings will be low. To increase your alkalinity, add pH buffer by mixing 1kg at a time in a bucket of water and spreading it all over the surface of the pool. Remember to never add more than 4kg in a 12 hour period. You may find pH increaser may incidentally increase your alkalinity but we do not recommend you use it as your only method of increasing alkalinity. If you have a high alkalinity reading, you more than likely have a high pH reading too. In order to bring both of these levels down, take the recommended hydrochloric acid dose from your Aquafirst water test results and split it into two. For example, the water test says add 800ml of acid, this means two doses of 400ml. The first dose should be spread all over the pool, covering as much surface area as possible. The second dose should be dumped in one area of the pool, simply stand in one spot next to the pool and pour straight down. By splitting the dose of hydrochloric acid and adding it in two ways, you will decrease your pH (the first dose) and alkalinity (the second dose) using only hydrochloric acid.  

Why do I almost always need to add pH buffer?

Most pools are sanitised with chlorine which is a highly alkaline compound. As chlorine is constantly added to the pool to maintain the sanitiser levels, alkalinity levels keep taking little hits each time and eventually they become too low.