What Causes Alkalinity to Drop in a Pool?

Your pool water must have the right amount of alkalinity at all times. Alkalinity is needed to neutralize acids, with bicarbonate, carbonate, and hydroxyl ions being the key elements in preventing pH levels from fluctuating too drastically. 

The ideal range of alkalinity for your pool should be between eighty and 120 parts per million (PPM). Long term and short term fluctuations naturally occur, which is why regular maintenance is necessary. Maintaining pool water chemistry is crucial to ensure a healthy pool, and it’s important to know how to increase and how to reduce alkalinity in a pool.

Here, we’ll look at the most common reasons for alkalinity levels to drop and take a look at ways to prevent the issue.

Causes of Alkalinity Drops in a Pool

There are many reasons the alkaline levels in your pool can drop. Some of these causes are due to natural circumstances, while others can be easily prevented.

Acid Rain

When acid rainwater enters the pool, it dilutes the water’s alkalinity levels which causes a drop. Acid rain is formed when natural or man-made pollutants like nitrogen oxide and sulfur dioxide mix with moisture in the atmosphere, resulting in rainfall polluted with harmful chemicals. You cannot directly prevent acid rain, but you can readjust your pool’s alkaline levels.

Heavy Rainfall

After a period of heavy rain, there is a significant chance that your pool will overflow, which brings in fresh water with lower alkalinity levels. Furthermore, heavy rainfall can bring with it pollutants such as fertilizers or pesticides from water runoff, which can result in an imbalance in the pool water chemistry.

Use of Acid-Based Chemicals

Using acid-based chemicals to adjust pool pH levels can significantly reduce the pool’s total alkalinity if used frequently. You should check how much muriatic acid is needed to lower alkalinity in a pool, along with any other chemicals you use. Familiarize yourself with which chemicals are needed to counterbalance and restore the pool’s alkalinity levels against those used to decrease them.

Leaks in Pool Equipment

Older and poorly maintained pools can develop leaks in the body of the pool or pool equipment. When pool water leaks, it is often replaced with natural water from rain. This often goes unnoticed, resulting in the alkalinity levels lowering over a period of time. 

General Impurities

When a pool is in use or exposed to the elements, impurities naturally find their way into the water. When swimmers enter the pool, they bring sweat, dirt, and urine, which contribute to the pool’s total alkalinity. General debris, such as leaves or sediment, can also cause alkalinity levels to drop. 

How to Prevent Decreases in Alkalinity

While you may not be able to control certain factors, such as acid rain or swimmer hygiene, there are steps you can take to maintain regular alkaline levels.

Testing and Monitoring

To stop alkalinity from dropping, regularly test and monitor the water. Testing kits are readily available for this purpose. Regular testing means you can detect, diagnose and correct problems before they become overly problematic. If your pool is used commercially, carry out tests more frequently, especially during periods of high activity. 

Pool Maintenance

Regularly maintaining your pool will help you maintain balanced alkaline levels. We recommend skimming and vacuuming your pool regularly to remove debris, dead insects, and other contaminants. Additionally, using the correct amount of chemicals is important to prevent fluctuations in the water chemistry. If necessary, you can hire an employee to check these levels and maintain your pool.

Use of Alkaline Products

To ensure proper alkalinity levels, use alkaline products specifically made for pool use. Sodium bicarbonate is a principal ingredient that will help maintain the alkalinity levels of your pool water. Read instructions carefully and be careful not to over treat your pool water.

In Summary

Alkalinity is an essential factor in correctly maintaining your pool. It’s important to understand how long it takes for alkalinity levels to drop and what is needed to ensure the alkalinity levels are optimum. If you notice any drop in alkaline levels, take the necessary steps to resolve the issue so that you can use your pool in a clean and safe manner.