If you own a pool, you know how important it is to keep the water balanced and clear. One of the key factors that affect your pool water quality is the total alkalinity. Total alkalinity is a measure of how much carbonate, bicarbonate, and hydroxide ions are present in the water. These ions act as a buffer to prevent sudden changes in the pH level of the water.
The ideal range for total alkalinity in a pool is between 80 and 120 parts per million (ppm). If the total alkalinity is too high, it can cause several problems, such as:
- Difficulty in adjusting the pH level
- Reduced effectiveness of chlorine
- Cloudy water
- Calcium scaling
- Corrosion of metal parts
- Irritation of skin and eyes
To avoid these issues, you need to lower the total alkalinity in your pool when it exceeds the recommended range. In this article, we will show you how to lower alkalinity in your pool using two proven methods: muriatic acid and sodium bisulfate. We will also explain how to restore your pH level without raising your alkalinity again.
Method 1: Use Muriatic Acid (Recommended)
Muriatic acid is a liquid form of hydrochloric acid that is commonly used to lower the total alkalinity and pH in pools. It is fast-acting and very effective, but it can also be dangerous if not handled properly. You should always wear protective gloves, goggles, and clothing when using muriatic acid. You should also follow the manufacturer’s instructions carefully and test the water frequently.
To lower the total alkalinity in your pool using muriatic acid, follow these steps:
- Test the water using a test kit or test strips to determine the current total alkalinity and pH levels.
- Calculate how much muriatic acid you need to add to your pool using an online calculator or a chart. The amount will depend on the size of your pool, the current total alkalinity, and the desired total alkalinity.
- Turn off the pump and heater and wait for the water to stop circulating.
- Pour the required amount of muriatic acid slowly and carefully into the deep end of the pool, away from any metal parts or fittings. Avoid splashing or spilling the acid on yourself or on any surfaces.
- Turn on the pump and heater and let the water circulate for at least 30 minutes.
- Test the water again to check the new total alkalinity and pH levels. If they are still too high, repeat steps 2 to 6 until you reach the desired levels.
Method 2: Use Sodium Bisulfate (Alternative)
Sodium bisulfate is a dry form of sulfuric acid that is also used to lower the total alkalinity and pH in pools. It is less potent and less hazardous than muriatic acid, but it can also take longer to work. You should still wear protective gloves, goggles, and clothing when using sodium bisulfate. You should also follow the manufacturer’s instructions carefully and test the water frequently.
To lower the total alkalinity in your pool using sodium bisulfate, follow these steps:
- Test the water using a test kit or test strips to determine the current total alkalinity and pH levels.
- Calculate how much sodium bisulfate you need to add to your pool using an online calculator or a chart. The amount will depend on the size of your pool, the current total alkalinity, and the desired total alkalinity.
- Turn off the pump and heater and wait for the water to stop circulating.
- Sprinkle the required amount of sodium bisulfate evenly over the surface of the pool, avoiding any metal parts or fittings.
- Turn on the pump and heater and let the water circulate for at least four hours.
- Test the water again to check the new total alkalinity and pH levels. If they are still too high, repeat steps 2 to 6 until you reach the desired levels.
How to Restore Your pH Level Without Raising Alkalinity
Both muriatic acid and sodium bisulfate will lower not only your total alkalinity but also your pH level. The ideal range for pH in a pool is between 7.4 and 7.6. If your pH level drops below this range, you need to raise it back up without affecting your total alkalinity.
The best way to do this is by aerating your pool water. Aeration is a process that increases the exposure of water to air, which raises the pH level naturally by releasing carbon dioxide from the water. Aeration does not affect your total alkalinity because it does not add any chemicals to your water.
To aerate your pool water, you can use any device or feature that creates bubbles or splashes in your water, such as:
- A pool fountain
- A water feature
- A spa jet
- An air compressor
- A pool brush
To raise your pH level using aeration, follow these steps:
- Test the water using a test kit or test strips to determine the current pH level.
- Turn on the device or feature that creates bubbles or splashes in your water and let it run for several hours.
- Test the water again to check the new pH level. If it is still too low, repeat steps 2 and 3 until you reach the desired level.
The Bottom Line
Keeping your total alkalinity in the ideal range is essential for maintaining a balanced and clear pool. If your total alkalinity is too high, you can lower it using muriatic acid or sodium bisulfate. Both of these methods will also lower your pH level, so you may need to restore it by aerating your pool water.
Remember to always test your water before and after adding any chemicals to your pool. You should also follow the safety precautions and instructions when handling any acids. By doing so, you can enjoy a healthy and sparkling pool all season long.