Before the pool water is considered safe for swimming, you need to adjust the chlorine and pH levels to prevent bacteria and algae from growing in your pool. You should never add all of the pool chemicals on the dame day because it will turn your water cloudy. Once you balance the pool water, you will need to make small adjustments throughout the season to keep your pool safe, sparkling and inviting.
Test the new water's chlorine level with your test kit. Follow the manual included with your kit for directions on how to collect and test a sample of water.
Add a chlorine shock treatment to boost te chlorine levels and kill bacteria and unwanted microbes. Read instructions on the packaging for proper amounts to add, based on the results of the test and the size of your pool. You can also use bleach as a substitute for shock treatment. Add about 1 gallon of bleach for every 10,000 gallons of water. Pool water should have a chlorine count of about 1 to 3 parts per million (ppm), but you can go above this since you won't be getting in the pool for a couple of days and some of the chlorine will evaporate.
Wait 24 hours after shocking your pool and test the water's pH level. Read the manual included with your kit for directions on testing pH. Most tap water will be close to 7.0, which is neutral, but pool water needs to be slightly alkaline with levels between 7.4 and 7.8.
Add baking soda to raise the pH level. Add 4 lbs. of baking soda for every 10,000 gallons of water if the pH level is below 7.2. Add 2 lbs. if the pH level is between 7.2 and 7.5. If your pool's pH level is above 7.8, add about 1 lb. of hydrochloric acid for every 10,000 gallons of water. If it is above 8.4, add 2 lbs. of hydrochloric acid for every 10,000 gallons of water.
Wait 24 hours and test your pool's pH and chlorine levels again. If both are at optimum levels, your pool is ready. If not, make necessary adjustments with the appropriate chemicals and wait another 24 hours. Once your pool water is safe for use, test it once a week and adjust the chemicals as needed.