Add potash. See your pool shop with a sample of your water and the size of your pool and he will give you what your pool requires.
Add acid
Muriatic Acid....Be real careful though.
Pool acid typically refers to muriatic acid, which is a common acid used to lower the pH levels in swimming pools. The main ingredient is hydrochloric acid. It is important to handle muriatic acid with care as it is highly corrosive and should be diluted before adding it to the pool water.
pool acid, also known as hydrochlorous acid, is actually a chlorinating agent, in addition to being an oxidizing agent. that is, it will *produce* some small amounts of aqueous chlorine, as opposed to eliminating it.
Hydrochloric acid is added to a pool to lower the pH level. Proper pH levels help maintain water clarity and prevent irritation to swimmers. It also helps in balancing other chemicals in the pool water and preventing the growth of harmful bacteria.
That Acid is called Muriatic Acid. You put it in your swimming pool to lower the PH of the water. At lower PH Levels, the chlorine you use to sanitize the pool is more active, as a disinfectant. You MUST be careful not to put too MUCH Muriatic Acid in your pool! PH that is too low will create potentially deadly fumes, so test your water. Low pH is corrosive to plaster and metal pool parst.
You lower the Ph by using Muriatic acid VERY carefully. This acid and it's vapour is dangerous. With the pool pump ON, carefully add 1/4 gallon at a time, waiting 6 hours then testing.
use either muriatic acid or dry acid (sodium bisulfate)
Using sodium bicarbonate to lower pH in a swimming pool is not effective. Sodium bicarbonate, or baking soda, is typically used to raise pH levels in pools. To lower pH in a pool, an acid such as muriatic acid or sodium bisulfate should be used.
No, muriatic acid and HTH stabilizer are not the same. Muriatic acid is a strong acid used to lower the pH of pool water, while HTH stabilizer (cyanuric acid) is used to prevent chlorine in the pool from being broken down by the sun's rays. Both serve different purposes in pool maintenance.
The only way to lower your cya level in your swimming pool is to partially drain your pool and fill with fresh water that will lower it or if you want to lower it to almost nothing completely drain your pool and start over but keep in mind chlorine tablets will raise your CYA level More information in the related link below.
It depends on the pH level in the pool and the gallons of the pools, also how many ppm you want to lower it.