It's advisable to add about 20 ounces of borax for every 5,000 gallons of water in your pool. This amount will help increase the pH by approximately 0.5.
After the first application of borax is dissolved, add the rest of the acid, followed by the rest of the borax. Brush again, and then keep the pump running for 24 to 48 hours. After 48 hours, test the water's pH and add more acid if necessary to bring the pH down to the correct level.
A rule of thumb is 1.5 lbs. of baking soda per 10,000 gallons of water will raise alkalinity by about 10 ppm. If your pool's pH tested below 7.2, add 3-4 pounds of baking soda. If you're new to adding pool chemicals, start by adding only one-half or three-fourths of the recommended amount.
If you're using borax to raise the pH of your pool water, you can add borax all by itself. If, however, your pH is fine but you're looking to add more alkalinity to buffer your pH, you may need to add borax with an acid to balance the pH.
For a 20,000 gal pool, about 60 lbs of Borax, and 4 gallons of acid.
If your pool has good circulation, then 30 minutes would be more than adequate to be safe.
To raise the pH levels in your pool, try adding sodium carbonate (soda ash) or sodium bicarbonate (baking soda) until your pool's pH levels are between 7.2 and 7.8.
Most pool experts recommend a pool pH between 7.2 and 7.8. To raise or lower pH, a pool custodian simply adds acids or alkalis into the water. For example, adding sodium carbonate (soda ash) or sodium bicarbonate (baking soda) will generally raise the pH, and adding muriatic acid or sodium bisulfate will lower the pH.
Use Aeration to Raise Pool pH
Looking to raise pH without affecting Total Alkalinity? You can sometimes raise the pH through aerating the pool water. Yep, just add air! It's the same reason hot tubs and spas often suffer from high pH issues.
There is no thing you can add to the water to raise pH without raising alkalinity, that would be impossible chemistry-wise. The only thing you can do is try to remove the acid (CO2) that's building up. The best thing to do would be to ignore it.
Soda Ash or Baking Soda? If you want to raise your pH and alkalinity together, use soda ash (sodium carbonate). If your goal is to raise alkalinity only, use baking soda (sodium bicarbonate).
Algae can raise the pH. Adding strong liquid chlorine, calcium or lithium hypochlorite chlorine may raise it. Suddenly heating the water, whether from a pool heater or a string of sunny days, could up the pH.
Low pH is bad for swimmers, your pool and your wallet. Acidic water is corrosive. The most immediate effect is felt by swimmers as the water will sting their eyes, nasal passages and will dry out skin and hair, causing itching.
For balanced pool water, keep the pH between pH of 7.4-7.6.
And there are two different chemicals you can use to raise the pH in your pool: Baking Soda aka sodium bicarbonate (sold as Alkalinity Increaser in pool stores). Soda Ash aka sodium carbonate (sold as pH Increaser in pool stores).
Unlike the carbonate compounds, borax prevents the pH from fluctuating without increasing the total alkalinity of the water. It also protects against algae growth by maintaining the pH at a constant level, allowing the chlorine to sanitize the water effectively.
Borates help in two ways: 1. They are good buffers, so generally prevent scaling 2. They lock up calcium almost like a chelate to prevent its formation In addition, borates in a pool can give the water a softer feeling, which is gentler on the skin.
Can you swim in a pool with high pH? Definitely, but know that chlorine in the water may not be as effective as it normally would and you may be exposing yourself to harmful microorganisms. Besides, the water can also turn cloudy and your pool sides may scale due to alkaline water.
Add vinegar to the water for an inexpensive fix.
The natural acidity of the vinegar will help neutralize the alkalinity in the water, bringing a pH of 7.5-7.7 down to about 5.8-6.0. Vinegar has a pH of 2-3 and lemon juice has a pH of 2, so their effect on water is similar.
Alkalinity is the total alkaline material in your pool water. You should test alkalinity first because it will buffer pH. Your reading should be in the range of 80 to 120 parts per million (ppm).
Causes of Rising Alkalinity
It's also not uncommon for pool owners to go a bit overboard when shocking their pool, and since chlorine-based pool shock is a high-alkaline substance, it will also naturally raise your pool alkalinity.
In theory, if you have a cloudy swimming pool, you can add chlorine to “shock it” and clear things up. Chlorine will get the job done. But, the amounts may vary and you may have to really pound the pool with chlorine to get the water totally clear.
In most cases, low pH levels are caused by natural factors like a heavy rainstorm, overuse, and improper use of chemicals. Natural rainwater has a pH of 5 – 5.5, so it is naturally acidic. A substantial amount of rainfall can alter the pH of pool water to become more acidic.
The only way to increase pH without increasing alkalinity is to reduce the CO2 dissolved in your tank. You could do this by using a CO2 scrubber or by running an air line outside. You could also install an air exchanger to reduce the overall CO2 level in your home.