What Happens When Alkalinity in Pool is Too High or Too Low?

Has your pool water turned cloudy or developed unsightly scaling on its surfaces? These are common signs of imbalanced pH and alkalinity levels. Mool equipment longevity, and, most importantly, your health. In this article, we will explore everything you need to know about alkalinity in pools, including causes of imbalance, potential effects, and how to correct alkalinity levels when they’re too high or too low.

What Is Alkalinity in a Pool?

Alkalinity in a pool refers to the concentration of alkaline substances, such as bicarbonates, carbonates, and hydroxides, which help stabilize the water’s pH. It essentially measures the pool’s ability to neutralize acids and bases, ensuring that the pH stays within the optimal range.

Alkalinity is measured in parts per million (ppm), with the recommended range for a pool being 80 to 120 ppm. Falling below 80 ppm leads to acidic water, while exceeding 120 ppm results in overly alkaline water. Both scenarios can cause adverse effects, which we’ll delve into later.

What Is Alkalinity in a Pool?

Causes of Low or High Alkalinity in Pools

Here's a detailed analysis of the causes of low and high alkalinity in swimming pools, presented in a more comprehensive format:

Causes of Low Alkalinity

Several factors can contribute to low alkalinity in your pool:

1. Excess Urine and Perspiration: These organic substances lower the alkaline content in the water.
2. Rainwater Runoff: Heavy rain can dilute the pool water, reducing its alkalinity levels.
3. Excess Chlorine Tablets: Many chlorine tablets contain low-pH chemicals, which can lead to a decrease in alkalinity.
4. Overuse of Dry Acid: Using too much dry acid to manage pH levels can inadvertently lower alkalinity.

Causes of High Alkalinity

High alkalinity levels often result from:

1. Oils, Lotions, and Sunscreen: Substances from swimmers’ skin and products mix into the water, affecting its chemical balance.
2. High-Alkaline Source Water: If your water supply has naturally high alkalinity, this can increase pool levels.
3. Excessive Shocking: Over-shocking the pool, especially after parties or heavy use, can disrupt the balance.

Why Is Alkalinity Important?

Alkalinity acts as a buffer for pH, preventing drastic changes when foreign substances enter the pool. Without proper alkalinity levels, maintaining a stable pH becomes challenging, leading to problems such as scaling, corrosion, or discomfort during swimming.

Why Is Alkalinity Important?

Is Alkalinity The Same as pH?

While alkalinity and pH are closely related, they are not the same. Here are the main differences between alkalinity and pH:

• pH measures how acidic or alkaline the water is on a scale of 1 to 14. A pH of 7, which is neutral, separates acidic solutions (pH below 7) from alkaline ones (pH above 7).
• Alkalinity measures the concentration of alkaline substances in the water, expressed in ppm.

For example:

• Lemon juice has a pH of 2 (highly acidic), while bleach has a pH of 13 (highly alkaline).
• Alkalinity stabilizes the pH to prevent sharp fluctuations caused by external factors.

Negative Effects of Alkalinity Imbalance

When alkalinity levels deviate from the recommended range of 80-120 ppm, it can trigger a cascade of problems affecting everything from pool surfaces to swimmer comfort. Let's examine in detail the specific negative effects of both low and high alkalinity levels:

Risks Posed by Low Alkalinity

1. Surface Damage: Acidic water can erode the pool’s surfaces, causing wear and tear.
2. Greenish Water: Algae growth is encouraged in acidic conditions.
3. Eye and Skin Irritation: Swimmers may experience discomfort or burning sensations.

Risks Posed by High Alkalinity

1. Scaling: High alkalinity causes calcium deposits and scaling on pool surfaces and equipment.
2. High pH: It becomes difficult to lower the pH level, requiring more chemicals.
3. Staining and Corrosion: Pool equipment and fixtures may suffer damage over time.

How to Test Pool Alkalinity

Testing pool alkalinity is a straightforward process:

1. Use a pool testing kit or digital pH sensor to measure the water’s alkalinity levels.
2. Ensure the ppm falls between the recommended range of 80 to 120 ppm.
3. Regular testing (at least once a week) helps maintain consistent water quality.

How to Test Pool Alkalinity

How to Raise Alkalinity Levels

When alkalinity in your pool is too low, you can increase it using sodium bicarbonate (commonly known as baking soda). Here’s how:

1. Test Alkalinity Levels: Measure the alkalinity to determine the required adjustment.
2. Purchase Baking Soda: Start with a 5-pound carton. Consult your pool supplier for precise quantities based on your pool size.
3. Add Gradually: Introduce half or three-quarters of the baking soda amount at first. Always dilute the baking soda before adding it to the water.
4. Retest: Wait for 6 to 24 hours before retesting the alkalinity. Repeat the process if necessary to achieve the desired ppm.

How to Lower Alkalinity Levels

If the alkalinity in your pool is too high, use dry acid (sodium bisulfate) to reduce it. Follow these steps:

1. Turn on the Pump: Ensure the water pump is running at maximum speed for proper circulation.
2. Add Dry Acid: Spread the acid evenly across the pool surface, allowing it to dissolve completely.
3. Monitor pH Levels: Use a testing kit to frequently check the water’s alkalinity and pH levels.
4. Avoid Overuse: Excessive dry acid can damage the pool’s surface, so add it gradually and retest frequently.

Tips for Keeping Alkalinity in Balance

The following comprehensive guide explores essential strategies for maintaining optimal alkalinity levels:

Regular Testing: The Cornerstone of Pool Care

Consistent monitoring of your pool's water chemistry is essential for maintaining balanced alkalinity. Invest in a reliable pool test kit and make it a habit to test your water regularly. This will allow you to identify any imbalances early on and take corrective action promptly.

Mindful Pool Usage: A Clean Pool is a Happy Pool

The activities in your pool can significantly impact its alkalinity. Oils, lotions, and debris from swimmers can introduce contaminants into the water, affecting its chemical balance. To mitigate this, make sure to clean your pool regularly, removing any debris that may accumulate. Additionally, consider limiting the number of swimmers in the pool at once to reduce the introduction of contaminants.

Weatherproofing Your Pool: Protecting Against Rainwater Dilution

Rainwater can dilute your pool's chemical balance, including its alkalinity. To safeguard your pool from this, invest in a high-quality pool cover. This protective barrier will prevent rainwater from entering your pool, ensuring that your water chemistry remains stable.

Chemical Wisdom: Less is Often More

While pool chemicals are crucial for maintaining water quality, it's important to use them judiciously. Overusing chemicals can lead to imbalances, including elevated alkalinity levels. Always follow the manufacturer's instructions carefully and avoid adding more chemicals than necessary. By using chemicals wisely, you can ensure optimal water chemistry and a healthy swimming environment.

Closing Thoughts

Maintaining the right alkalinity in your pool is key to enjoying a clean, safe, and comfortable swimming experience. By keeping total alkalinity within the ideal range of 80 to 120 ppm, you prevent a host of issues, from cloudy water to equipment damage. Regular testing and timely adjustments with baking soda or dry acid ensure that your pool remains in top condition. With consistent care and attention, you can make pool maintenance an easy and stress-free task.

Whether your alkalinity in the pool is high or alkalinity in the pool is low, balancing the water chemistry is always the solution. Monitor regularly, act promptly, and enjoy your sparkling pool year-round!