Any pool owner should be fully aware of the pool water's pH level at all times. When pool water is on the lower, acidic, range of the pH scale it can cause irritation to the eyes and skin, which makes for an overall unpleasant experience. You can buy dozens of products from pool supply stores to help raise pH levels but they sometimes come with a hefty price tag. An inexpensive solution to low pH is adding borax to the water.
Test the pH level of the water. The ideal pH range is between 7.4 and 7.6.
Measure the amount of borax needed to raise the pH level to the ideal range. For every 5,000 gallons of water in the pool, add 20 oz. of borax to raise the pH level by as much as 0.5. The exact amount the pH increases differs depending on the chemical makeup of the water, so it's best to underestimate. It's easier to add more borax to the pool later on than to decrease the pH with other products.
Turn on the pool's water pump to promote water circulation.
Pour the borax into the deepest part of the pool. Let the pump run for a minimum of 72 hours to ensure the borax is fully incorporated and settles.
Check the pH level after the 72 hour period. If necessary, add more borax to increase to the water using the same technique as the first time.