2. Dichloroisocyanuric Acid: Also known as “dichlor,” this is another type of chlorine shock. Dichlor contains both chlorine and cyanuric acid and will, over time, raise your cyanuric acid levels.
Shock does not contain any cyanuric acid, so after 24 hours, the elevated amounts of chlorine are no longer in the pool.
It lowers the overall pH levels, however using Di-Chlor Shock will add CYA or Cyanuric Acid (commonly referred to as water conditioner). CYA prevents chemical loss due to evaporation, but too much can reduce the effectiveness of your free chlorine, allowing algae to grow.
Cyanuric acid is raised by adding chlorine stabilizer containing cyanuric acid. The only way to lower cyanuric acid is by replacing water.
So, chlorine tabs lower pH and Total Alkalinity and increase cyanuric acid levels.
You do need to use both tabs and shock. Without tabs, the chlorine shock will dissipate quickly out of the water; without shock, the chlorine level will not get high enough to fully sanitize the water.
Does Muriatic Acid Affect Cyanuric Acid? Both muriatic acid and cyanuric acid can be used in your pool with minimal adverse effects on each other. Although, as with any chemical, it's best not to dump a whole lot into your pool at the one time or mix chemicals.
As mentioned earlier, it will take at least 48 hours and up to a week to fully dissolve. Powdered cyanuric acid is not so common and it may not be available to buy in your area. It's reported to not dissolve any faster than granular stabilizer.
In addition to raising available chlorine, cal hypo boosts pH, alkalinity and calcium hardness (CH) levels. Trichlor has the opposite effect on pH and alkalinity — reducing it. And where cal hypo affects CH, trichlor increases cyanuric acid (CYA).
Saltwater pool manufacturers recommend maintaining cyanuric acid levels around 60-80 ppm. This is a bit higher than the 30-50 ppm range recommended for non-saltwater pools. And if you live in an area where your pool gets a lot of direct sunlight, you may even consider bumping your cyanuric acid up to 80-100 ppm.
Why You Have Low Cyanuric Acid
The most likely reason is that you've only ever used unstabilized chlorine in your pool. Heads up: Unstabilized chlorine, such as sodium hypochlorite (liquid chlorine), lithium hypochlorite, and calcium hypochlorite, is pure chlorine.
You should keep your outdoor pool or spa's Cyanuric Acid level at 0-30 parts per million (PPM).
No, cyanuric acid and baking soda work in very different ways in your pool. Baking soda raises the total alkalinity in your pool. But baking soda does not protect or stabilize your chlorine, like CYA.
Do you need cyanuric acid in a spa or hot tub? Yes! If you are using a chlorine sanitiser, you do need to use cyanuric acid to get help your chlorine work efficiently. Without cyanuric acid, your chlorine level can drop from the ideal range to zero in less than two hours when exposed to the sun.
The main reason for high CYA levels in your pool is from using too much stabilized chlorine. When the pool water evaporates, CYA remains in the water, much like other chemicals such as salt and calcium. As an example, 1 lb. of trichlor in a 10,000 gallon pool will raise the CYA level by 6 ppm.
Shock has a more intense chemical strength than the traditional chlorine sanitizers, and it also differs in how you should apply it to your swimming pool. Short answer: No. Chlorine sanitizers and shock are similar but different in strength.
Backwash only as needed. Brush the pool vigorously, several times after shocking the pool. Do not use a solar blanket until chlorine and pH level are normal. If chlorine level drops to zero within 24 hours, Repeat the shock treatment.
Liquid chlorine and granular shock have the same active chemical that sanitizes your pool, what changes is the strength and the way you use it. Liquid chlorine is less costly, unstabilized and comes in liquid form. Granular shock is stabilized and comes in a solid form that dissolves in your pool.
Cyanuric acid is available as a granular solid and as a liquid (sodium cyanurate). Most commonly, however, cyanuric acid is found in stabilized chlorines dichlor and trichlor. These stabilized chlorines have about 50-58% CYA in their formulas.
Use test kits or strips designed to measure cyanuric acid, so you can determine how much acid to add to your pool. To significantly raise levels, dissolve powdered cyanuric acid or add a liquid version. You can also add stabilized chlorine for regular maintenance.
Answer: Cyanuric acid shouldn't be at Zero for an outdoor swimming pool because chlorine will deplete faster in hot and humid weather, leading to cloudy water. If your FC is at normal level of 3ppm, raise Cyanuric acid level to 40 ppm and you will reduce chloramine levels that make your water appear cloudy.
Cal hypo does not contain stabilizer (cyanuric acid), though it can be stabilized toward sunlight in recreational water through the use of cyanuric acid. You can buy it in slow dissolving tablet forms, or more rapidly dissolving granular forms, depending on your needs.
Unstabilized chlorine is simply chlorine that has not had cyanuric acid added to it. This means it dissipates more quickly, you won't get as much sanitizing power, and you'll have to add more chlorine more often. So if it's vulnerable to the sun, why would you use unstabilized chlorine?