Owning a pool requires a bit of know-how and experience to keep in working order. Most pool owners know that chemical balance is the most important part of maintaining a swimming pool. Bacteria, algae, mold, and other potentially dangerous pathogens can all easily make their home in untreated water which can make cause those who swim in it to get sick, have skin irritation, and more. This is why chemicals are such an important part of pool care.
It might be best to think of pool water as a solution or mixture rather than water. The water is kept sanitized through the use of several different chemicals that keep the water sanitized, meaning that the chemical levels in the water are enough to kill anything nasty that could cause harm. Those who have automatic chemical feeding systems might think that all they have to do is keep their drums full and they are good, but this would be a bad thing to assume.
There are a lot of factors that determine the chemical balance of your pool. The amount of rain you have gotten, how intense and prolonged sun exposure is, the number of people swimming in the pool, people swimming in the pool with shampoo, sweat, makeup, or other residues on their skin or hair – all of these things can affect the way chemicals work in your pool and can leave it less able to keep up with the water’s chemical needs.
Pool Chemicals
Chances are when you think of pool chemicals, you automatically think of chlorine. Chlorine is incredibly important. Its very structure allows it to destroy the outer membranes of dangerous pathogens and other substances, killing them and rendering them harmless. However, chlorine is not the only chemical you will use in your pool. You will also use some form of acid. This helps to keep the pH balanced and helps keep the chlorine active and thus able to do its job sanitizing.
There are two main types of acid used in pool systems: muriatic and cyanuric acid. For people who have outdoor pools, cyanuric acid is the most commonly used type of acid. Sometimes cyanuric acid is referred to as a pool stabilizer. In essence, cyanuric acid acts as an “assistant” to the chlorine. It is called a stabilizer because of it its job, the cyanuric acid helps to stabilize the chlorine so that the chlorine can stay active in your pool longer.
Cyanuric Acid Basics
Cyanuric acid is a compound called a triazine. This simply means that it has three nitrogen and three carbon atoms. You can find this at any quality pool supply store, but it could go under many different names. Sometimes it is sold as cyanuric acid, CYA, pool stabilizer, chlorine stabilizer, or pool conditioner. Regardless of what they call it, all of these are the same thing. There are even chlorine erosion tablets that already have cyanuric acid in them.
You can buy cyanuric acid in liquid or granule form. Either form works just fine, it depends on your preferences. Some people rely on pre-mixed products that have both chlorine and cyanuric acid. It can be easier to maintain the right levels of chemicals in the pool if you use separate products, but it is up to each person.
The Value of Cyanuric Acid
Cyanuric acid effects chlorine and that is the reason you use it in your pool. There are three main types of chlorine in pool water: combined chlorine, total chlorine, and free chlorine.
Combined Chlorine
This is simply a measure of the amount of chlorine that has been “used up” sanitizing the water. What this means is that the chlorine is still in the water, but it no longer has sanitation capability.
Total Chlorine
As the name implies, this measure simply refers to the total amount of chlorine in your pool. This is a total of both combined chlorine, which has been used up, and free chlorine.
Free Chlorine
Free chlorine can also be thought of as active chlorine. When you do a water test to measure free chlorine, you are measuring the amount of active chlorine in the water that is capable of sanitization. This is an incredibly important measure as it gives you an idea of how much of the chlorine in your water is still active.
Chlorine turns into sodium hypochlorite ions in the water and these are what seek out and destroy bacteria and other pathogens. The thing is though that sunlight (UV rays) cause chlorine to break down. This causes the chlorine to evaporate and reduces the amount of free chlorine in your water. During intensely sunny periods, without any stabilizer, almost half of the free chlorine in a pool can be destroyed in less than 20 minutes.
Cyanuric acid works to help combat this process, stabilizing the chlorine and allowing it to remain active for longer. Additionally, cyanuric acid also helps to amplify the effects of chlorine. Some statistics show that you could need to use as much as 8 times more chlorine to keep your pool sanitized with chlorine alone than if you use it in conjunction with cyanuric acid. Cyanuric acid not only helps keep the chlorine-free and active, but it also lowers the overall chlorine demands of the pool system.
A Note on the Cons of Cyanuric Acid
While cyanuric acid is an incredibly useful chemical to use in your pool, it is not without its problems and it helps to be aware of this. The ability of chlorine to do its job is called an oxidation-reduction potential (ORP for pool geeks). This measure tells you how well your chlorine is doing in its ability to sanitize. Cyanuric acid, regardless of how much you use, will lower the ORP of the water. This can, over time, actually work to reduce the effectiveness of chlorine as the stabilizer will render the chlorine inert (making it into combined chlorine) which, no matter how much more chlorine you add, will not be able to sanitize the water.
Though this might make some question whether they want to use cyanuric acid, this isn’t said to make you reconsider its use. It is still one of the most effective ways to keep your chlorine active, even during sunny weather conditions. The point of bringing up the negative aspects is to show that there is most definitely such thing as too much cyanuric acid and that it requires testing and experience to keep a good balance between cyanuric acid and chlorine in your pool.