The pH scale measures the concentration of hydrogen ions in water, determining its acidity or alkalinity, ranging from 0 to 14. A value of 7.0 is neutral; numbers below 7 indicate increasing acidity, and numbers above 7 indicate increasing alkalinity (basicity). “pH balanced water” typically refers to water that is neutral or slightly alkaline, generally falling within the recommended drinking water range of 6.5 to 8.5. This range minimizes plumbing corrosion and ensures the water is pleasant to consume. Understanding how to safely adjust the pH of water at home allows for customization based on personal preference or household needs.
Determining the Current pH Level
Before modifying water chemistry, determine the starting pH value. The pH scale is logarithmic, meaning a shift of one whole number represents a tenfold difference in acidity or alkalinity. Accurate measurement is important before making any adjustment.
Home testing tools include pH test strips or liquid test kits, which compare a color change to a reference chart. While inexpensive, these methods offer lower precision than electronic devices. For a more precise measurement, a digital pH meter uses an electrode to provide a numerical reading of the hydrogen ion activity.
A reading of 7.0 confirms a neutral state. A reading of 6.0 indicates water ten times more acidic than neutral, while 8.0 indicates water ten times more alkaline. Knowing this baseline allows for a controlled adjustment toward the desired 7.0 to 8.5 range.
DIY Methods for Increasing Water pH
The goal for many is to increase alkalinity using common household items. A simple and effective method is adding sodium bicarbonate, commonly known as baking soda, which is naturally alkaline with a pH of approximately 9.
To raise the pH of drinking water, dissolve about \(\frac{1}{8}\) teaspoon of baking soda into 8 ounces (\(240\text{ mL}\)) of filtered water. Alternatively, \(\frac{1}{4}\) teaspoon can be mixed into 1 liter of water, typically raising the pH to around 8.5. Stir the mixture until the powder is completely dissolved for a uniform solution.
Another convenient method involves using concentrated mineral solutions, often sold as pH drops. These drops contain electrolytes and minerals designed to boost alkalinity. The exact number of drops needed varies depending on the product’s concentration and the volume of water, so following the manufacturer’s directions is necessary.
The use of lemon or lime juice is sometimes suggested for alkalizing water, though this process is often misunderstood. Lemon juice is initially acidic (pH 2 to 3). When consumed, the body metabolizes the juice, producing alkaline byproducts that can have an overall alkalizing effect internally. Squeezing the juice of half a lemon into water creates a refreshing drink, but it does not directly increase the pH of the water itself.
Adjusting Water pH for Specific Applications
While many seek to raise the pH for drinking, lowering the pH (acidification) is desirable for specific non-ingestion applications. These include cleaning tasks, specialized plant care, or maintaining aquatic environments.
For lowering the pH of water used in gardening or for houseplants that thrive in acidic soil, white vinegar is a readily available option. Adding approximately 1 tablespoon of white vinegar to 1 gallon of water can effectively lower the pH from a slightly alkaline range (7.5 to 7.7) down to an acidic range (5.8 to 6.0). This adjustment assists in making certain soil nutrients more available for plants to absorb.
For aquariums, specialized methods achieve the slightly acidic conditions preferred by some fish species. Reverse osmosis (RO) systems are common, as this filtration removes dissolved minerals that normally act as buffers, often resulting in slightly acidic water. Introducing organic materials like peat moss or driftwood will also slowly release tannins, which are weak organic acids that naturally reduce the water’s pH.
Safety and Stability of Adjusted Water
When altering water pH, safety and stability are important considerations. The recommended pH range for drinking water is 6.5 to 8.5. Water that is too acidic (below 6.5) can become corrosive, potentially leaching heavy metals from plumbing fixtures into the water supply.
Conversely, water that is excessively alkaline (above 8.5) can lead to mineral scaling in pipes and may impart an unpleasant soapy or bitter taste. Ensure that the source water used for adjustment is potable and safe before modification. If using baking soda, individuals on a low-sodium diet should be mindful of the added sodium content.
The stability of the adjusted pH level is influenced by the water’s natural buffering capacity—its ability to resist changes in pH. Water with a high concentration of dissolved minerals, known as carbonate hardness, will naturally resist pH changes and may cause the adjusted level to revert over time. Adjusted water should be stored in a clean, airtight container and consumed relatively soon after preparation.