How to Fix Low pH in Drinking Water Effectively

According to the EPA, ideal drinking water pH should be between 6.5 and 8.5. Low pH water, which is acidic, can leach heavy metals from your plumbing and cause corrosion. Fortunately, there are several reliable methods for how to fix low pH in drinking water and safeguard your family's health and home.

Quick Summary

Neutralizing acidic drinking water requires strategic treatment to prevent plumbing corrosion and metal leaching. This guide outlines popular methods like whole-house filters and chemical injection systems for effective pH balance. Learn about the risks of low pH and find the right solution for your home's water supply.

Key Points

• Test Your Water: Begin by testing your water's pH to confirm if it is below the EPA's recommended 6.5-8.5 range.

• Address Corrosion: Low pH water is corrosive, causing damage to metal pipes, which leads to pinhole leaks and blue-green stains.

• Choose a Whole-House Filter: Calcite neutralizing filters are ideal for moderately acidic water, but will increase water hardness.

• Consider Chemical Injection: For severely acidic water or to avoid increased hardness, a soda ash injection system offers precise control.

• Avoid Heavy Metals: Acidic water leaches heavy metals like copper and lead from plumbing, posing significant health risks.

• Perform Regular Maintenance: Both filtration and injection systems require routine media or chemical replenishment to remain effective.

Understanding the Problem: Why Low pH Water is a Concern

Low pH water is acidic and often called "hungry water" due to its corrosive nature. When it flows through your plumbing, it actively tries to rebalance itself by dissolving metal, which can lead to significant problems over time.

Signs of Acidic Water

• Metallic or sour taste: A bitter or sour flavor can indicate the presence of dissolved metals, such as copper or zinc.
• Blue-green or rust stains: Blue-green stains on sinks, showers, and faucets are a tell-tale sign of corroded copper pipes, while rust-colored stains point to galvanized steel or iron.
• Pinhole leaks in plumbing: Over time, acidic water eats away at pipes, causing small, localized leaks that can lead to major water damage.
• Premature appliance failure: Water heaters and other water-using appliances can be damaged by corrosion, shortening their lifespan.
• Elevated heavy metal levels: The most serious risk is the leaching of lead, copper, and other heavy metals into your drinking supply, which can cause significant health issues.

Solutions for Low pH Water

There are two primary, long-term solutions for correcting low pH in your entire home water supply: neutralizing filters and chemical injection systems. For temporary, small-batch corrections, there are also simpler methods.

Method 1: Neutralizing Filters

For moderately acidic water (typically pH 6.0 to 6.9), a neutralizing filter is a very common and effective solution.

How it works

1. A large tank is filled with a neutralizing media, most commonly calcite (calcium carbonate) or a blend of calcite and Corosex (magnesium oxide).
2. As water flows through the media, the acidic water dissolves a small amount of the calcite, raising the water's pH.
3. The water exits the tank with a more neutral pH, no longer corrosive.

Key considerations

• Replenishment: The media in the tank is gradually used up and must be refilled, typically every 6 to 12 months, depending on your water usage and acidity level.
• Water Hardness: Since calcite adds calcium to the water, it will increase your water's hardness. You may need a water softener installed after the neutralizer, especially if your water was already hard.
• Flow rates: For very low pH water (below 6.0), blending calcite with Corosex is often necessary for more aggressive correction.

Method 2: Chemical Injection Systems

For very acidic water (typically pH below 6.0) or situations where adding hardness is undesirable, a chemical injection system is the preferred option.

How it works

1. A chemical feed pump (often a Stenner or other diaphragm pump) is used to precisely inject a basic solution into your water line.
2. The most common solution is soda ash (sodium carbonate). Caustic soda (sodium hydroxide) is also used in some commercial applications but requires more careful handling.
3. A retention tank is used after injection to ensure the chemical has enough time to react and stabilize the pH before it reaches your taps.

Key considerations

• Professional installation: Due to the nature of chemical handling and precise dosing, professional installation is often recommended.
• No hardness increase: Unlike neutralizing filters, soda ash injection does not significantly increase water hardness.
• Cost and maintenance: While a larger upfront investment, this method offers more precise control. It does require regular monitoring and refilling of the chemical solution.

Quick and Temporary Fixes (for single use)

For a glass or pitcher of water, you can make a temporary adjustment. These methods are not for continuous use and should not be relied on to fix your household's overall plumbing corrosion issue.

• Add baking soda: Add about 1/4 teaspoon of baking soda to a gallon of water and stir thoroughly. Test the water to ensure you haven't over-corrected the pH, as baking soda is a strong buffer.
• Alkaline drops: Specific pH-boosting drops are available commercially in health food stores and online for single servings of water.

Comparison of pH Correction Methods

Feature	Calcite Neutralizing Filter	Soda Ash Injection System	DIY Methods (Baking Soda)
Effectiveness	Excellent for moderately acidic water (pH 6.0-6.9).	Excellent for very low pH water (below 6.0), provides precise control.	Limited to small batches and temporary use; not for continuous correction.
Mechanism	Water flows over and dissolves natural calcite media.	A pump injects a measured amount of soda ash solution.	Manually stirs baking soda into water.
Corrosion Prevention	Effective throughout the entire plumbing system.	Effective throughout the entire plumbing system.	Does not address system-wide corrosion.
Maintenance	Requires periodic refilling of media (6-12 months).	Requires monitoring and refilling of chemical solution tank.	No system maintenance required, but manual for each batch.
Impact on Water Hardness	Increases water hardness, may require a water softener.	Does not increase water hardness.	Increases sodium content, can affect taste.
Installation	Professional installation often recommended.	Requires professional installation for safety and accuracy.	No installation required.
Best For	Mildly acidic well water where a hardness increase is acceptable.	Very acidic water or soft water where hardness addition is unwanted.	Short-term, single-batch treatment, or emergency use only.

Conclusion: Choosing the Right Solution

Addressing low pH in drinking water is critical to protecting your home's plumbing and ensuring safe consumption. The right method depends on the severity of your water's acidity and your preferences regarding water hardness. For most residential properties with mildly acidic water, a calcite neutralizing filter is a low-maintenance and effective option. For severely acidic water or where soft water is desired, a soda ash injection system provides more powerful, controlled treatment. While quick fixes like baking soda can help in a pinch, they are not a substitute for a whole-house treatment system. To start, get your water tested by a professional to determine the best course of action. For further details on water quality standards, consider consulting resources like the U.S. Environmental Protection Agency's Secondary Drinking Water Standards guide.

What to do if you suspect you have acidic water

• Test your water's pH: Use a home test kit or, for more accuracy, have a professional test your water.
• Inspect your plumbing: Look for blue-green stains around sinks or fixtures, which indicate copper corrosion.
• Consult a water treatment specialist: Discuss the results of your water test and explore the best long-term solution for your home.
• Choose a method: Based on your water's specific chemistry, decide between a neutralizing filter or a chemical injection system.
• Follow maintenance guidelines: Whichever system you choose, be sure to perform regular maintenance to ensure its continued effectiveness.

Final thoughts on water corrosivity

Remember that low pH is just one factor in water corrosivity. Other elements, like alkalinity and temperature, also play a role. A comprehensive water test will give you the full picture. By taking proactive steps to correct low pH, you not only improve the quality and safety of your drinking water but also prevent costly damage to your home's infrastructure.

Frequently Asked Questions

What is considered low pH for drinking water?

A pH level below 6.5 is generally considered acidic and low for drinking water, indicating it could be corrosive and potentially leach metals from plumbing.

Does low pH water have health risks?

While low pH itself is not a direct health risk, its corrosive nature can leach heavy metals like copper and lead from your pipes into your water, which can be harmful if consumed over time.

Can I use baking soda for a permanent fix?

No, adding baking soda is only a temporary, small-batch solution and will not protect your entire plumbing system from the long-term corrosive effects of acidic water.

How do calcite neutralizing filters work?

Calcite filters contain a natural calcium carbonate media. As acidic water passes through, it dissolves the media, which releases calcium and raises the water's pH.

What are the downsides of a calcite neutralizer?

The main downside is that it increases water hardness, which may require a water softener to be installed in conjunction with the neutralizer, especially if your water was already hard.

When is a soda ash injection system better?

A soda ash injection system is better for very acidic water (pH below 6.0) or when you want to raise the pH without increasing water hardness.

Is a chemical injection system safe for drinking water?

Yes, when correctly dosed with NSF-certified chemicals like soda ash, chemical injection systems are safe and widely used to neutralize drinking water.

How do I know if my pipes are corroding?

Look for blue-green stains on fixtures or a metallic taste in your water. In severe cases, you may also experience frequent pinhole leaks in your plumbing.