Chemical additives and contaminants can cause swimming pool water to become too alkaline, meaning its pH level is too high. The CDC (United States health agency) recommends maintaining a swimming pool's pH level between 7.2 and 7.8 to prevent eye and skin irritation, maintain pool sanitation, and prevent damage to pools and fittings. Test pool water regularly to detect pool pH levels that are too high. Lowering the pH level can be done with hydrochloric acid (muriatic) or sodium bisulfate, or consider installing a CO2 system to maintain an ideal pH level.
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Method 1 of 4: Testing the Pond's pH Level
Step 1. Get the DPD test kit
While there are many types of devices on the market for testing pool pH (including digital testers and litmus strips) DPD test kits provide the most accurate results. The price of this device is also affordable compared to digital testing devices. You can buy this test kit at a supermarket or home supply store. These chemicals contain a variety of chemicals that change color when mixed with pool water. These chemicals test the quality of pool water, such as pH, total alkalinity, chlorine and bromine levels, and water hardness.
- A wide variety of DPD test kits are available in various forms. For example, some use liquid reagents, while others use solid tablets.
- Liquid and tablet test kits have a similar level of accuracy, but tablets are easier to use because they don't require exact measurements of liquid reagents
- Although litmus strips are easier to use than DPD kits, when used properly, DPD kits provide more accurate results.
- Digital testing kits do not have a clear mechanism to indicate inaccurate test results (eg the color of the test results do not match the test chart) so that the results can be misleading.
Step 2. Follow the test device usage guide
The DPD test kit can be used by mixing various chemical reagents with a sample of pond water. These chemicals change color when mixed with pool water, and you must match them to the colors on the chart to determine the results
- Read the user manual carefully to make sure the device is used properly and that you know how to interpret the results.
- Make sure you are using the correct reagent to test the pH level. Most devices use Phenol Red for this reason.
Step 3. Watch out for erroneous or problematic results
Most pool pH testers appear more yellow if the level is low, and red if the level is high. However, if the pool water contains very high levels of chlorine or bromine, the test may be interrupted and give strange results, such as turning purple in color. The low alkalinity also makes the test results inaccurate. To minimize this problem, test for chlorine, bromine, and total alkalinity before testing the pH.
Test kits can also give inaccurate results if reagents are not stored properly (eg in humid or extreme areas), or become contaminated as a result of careless handling
Step 4. Test the pool of water twice a week
Most experts recommend testing pool water 2-3 times a week, especially during the summer, when the pool is used very often. The CDC recommends testing pool water twice a day or more frequently when the pool is used every day or many people throughout the day.
The pH level of the pool needs to be checked more often when the pool is being used a lot because any elements that enter the pool water, such as natural oils from the swimmer's hair and body, residual sunscreen and other body care products, or dirt entering the pool) will affect the chemical composition of the water. pool
Method 2 of 4: Using Hydrochloric Acid to Lower the pH
Step 1. Purchase hydrochloric acid specifically formulated for pool water
Hydrochloric acid, also known as hydrochloric acid, is a corrosive chemical with multiple functions. To make sure you're getting the right concentration of hydrochloric acid for your swimming pool, buy a product made specifically for pool water. Most home and pool supply stores provide muric acid for swimming pools.
Step 2. Read the guide label carefully
Various products are sold in various concentrations and forms. Some pH-reducing hydrochloric acid is sold as a ready-to-use solution, while others are in granular form. Read all product safety guidelines and make sure you understand exactly how to use a particular product before using it in a pool.
Some forms of hydrochloric acid can be mixed directly into pool water, while others must be diluted in a bucket before use
Step 3. Take appropriate precautions
Even dilute hydrochloric acid can burn eyes and skin. If inhaled, the fumes of this acid can also irritate the nose, throat and lungs. Before handling hydrochloric acid, wear rubber gloves and clothing that covers your arms, legs, and soles. Wear a respirator mask and safety glasses. Handling of hydrochloric acid should always be carried out in a well-ventilated area.
- If you get hydrochloric acid in your eyes, rinse immediately with cool, clean water for at least 15 minutes, then seek medical attention.
- If hydrochloric acid gets on the skin, rinse with cool, clean water for at least 15 minutes, and remove all clothing that has been exposed to the acid. If so, seek medical attention immediately.
- Get medical attention if you swallow the acid or breathe its fumes.
Step 4. Determine how much acid you need to add
Check the directions for use on the hydrochloric acid product label to find out how much acid to add depending on the size of the pool and the current pH of the water. Try adding about of the recommended amount to prevent the pH level from dropping too much.
You can also estimate the amount of acid added by using an online calculator, for example:
Step 5. Pour the acid into the pool via the return jet
While the return jet is on and the vent is facing down, slowly and carefully pour the acid directly into the jet. Backflow will distribute the pool evenly throughout the pool.
- Hold the container close to the water when pouring the acid so it doesn't splash.
- Be careful not to let the acid pass through the pool fittings or directly touch the pool walls.
Step 6. Test the pool pH again after 4 hours
If the hydrochloric acid has been circulating long enough, test the pH again. If it's still too high, repeat the procedure, using the recommended amount of acid for the new pool's pH level.
Step 7. Wait at least 4 hours since the last pour of acid before the pool can be used again
During this time, the hydrochloric acid should be evenly distributed before the pool can be used for swimming. Otherwise, swimmers run the risk of entering a "pocket" of concentrated acid in the water. Keep the pump and jet running while you wait for the acid to work through the water.
Method 3 of 4: Lowering the pH with Sodium Bisulfate
Step 1. Purchase sodium bisulfate or “dry acid”
Sodium bisulfate is an acid that is sold in the form of granules or powder. This product is safer and gentler than hydrochloric acid. Sodium bisulfate for pools is available at most pool and home supply stores.
Step 2. Follow the instructions on the package
Different manufacturers may provide different user guides. In some cases, you may need to dissolve the sodium bisulfate in the water before adding it to the pool, while in others it can be added directly to the pool as a powder.
Step 3. Determine the amount of sodium bisulfate to be added
Follow the product manual to determine the amount of sodium bisulfate based on the size of the pool and the current pH of the water. You can use of the manufacturer's recommended amount to prevent the pH level from dropping too much.
You can also use a pool calculator, for example:
Step 4. Implement preventive measures
Sodium bisulfate is a fairly gentle substance, but it can still cause serious burns and irritation. Wear gloves and clothing that covers the entire skin, such as long sleeves and long pants. You must work in a well-ventilated area. If you don't want the acid droplets to blow onto your face, wear safety glasses or a face shield.
- If sodium bisulfate gets on the skin, wash it thoroughly with soap and water. See a doctor if you experience skin irritation and it doesn't go away after washing.
- If you get sodium bisulfate in your eyes, rinse with cold water for at least 15 minutes, then seek medical attention immediately.
- If the powder is ingested, rinse your mouth with water and drink at least one tall glass of water. Get medical care immediately.
Step 5. Pour the dry acid into the pond via a return jet
While the pump and jet are running, slowly introduce the acid into the pool via the return jet. Be sure to keep the powder out of the skimmer.
Try to pour the substance as close to the water as possible so it doesn't splash, and make sure the powder doesn't blow towards you
Step 6. Wait for a few hours and test the pH level again
Since sodium bisulfate can also lower total alkalinity, you should also test it and make sure it's within the ideal range for your swimming pool. Make adjustments based on test results, if necessary.
Do not wait more than 24 hours after adding dry acid before testing the pool pH level again
Step 7. Add alkalinity enhancer immediately, if possible
If the total alkalinity is too low after adding sodium bisulfate, increase it by adding an alkalinity enhancer, such as baking soda or sodium sesquicarbonate (sesquicarbonate) to the pool water. Alkalinity enhancers can be found at most pool and home supply stores.
- Soda ash can also increase the total alkalinity of the pool, but it can bring the pH of the water back up.
- Follow the manufacturer's instructions for use to determine the amount of alkalinity enhancer required for the size and current total alkalinity of the pond. If you use regular baking soda, please use an online calculator, for example:
Step 8. Wait at least 4 hours before returning to swimming
Although sodium bisulfate is mild, it can still irritate the skin and eyes. Give the acid enough time to dissolve and circulate throughout your pool before it can swim again.
Method 4 of 4: Installing a CO2 System in a Swimming Pool
Step 1. Purchase a CO2 system to maintain a safe pH level in the pond
Carbon dioxide, aka CO2, can effectively lower and stabilize pool pH levels. There are many CO2 systems for ponds available, and some can effectively analyze pond pH levels and adjust output accordingly. These devices can be purchased at specialty pool and spa supply stores.
- Some CO2 systems are fully automated, while others still need to be manually controlled. Consult an expert at a pool supply store to determine the best type of CO2 for your pool.
- The price of this system can be expensive, between IDR 4,500,000-IDR 150,000,000. However, a CO2 system can save costs in the long run as it minimizes the need for adjustment of pH and chlorine levels.
Step 2. Use a professional to install the system
Unless you are very experienced in installing swimming pool equipment, we recommend hiring a professional technician to install a CO2 system. Consider consulting an expert before purchasing a CO2 system to help determine the best system for your swimming pool.
Step 3. Avoid using a CO2 system if the water is very hard or contains a high total alkalinity
Since CO2 can increase the total alkalinity of the pond, it is best not to use a CO2 system if the total alkalinity of the pond is already high (i.e. above 125 ppm). CO2 is also not very effective in lowering the pH if the water is hard. Consult an expert to determine the right water conditions for the CO2 system.
