Water’s acidity or alkalinity is measured by its pH level. The term “basic” or “alkaline” refers to water with a pH greater than 7.0, indicating a relative abundance of hydroxide ions. Many people seek to increase their water’s pH for various reasons, including taste preference or perceived health benefits.
The pH Scale and What Defines Basic Water
The pH scale is a logarithmic index running from 0 to 14 that quantifies the concentration of hydrogen ions (H+) in a solution. A value of 7.0 represents chemical neutrality, where the concentrations of positively charged hydrogen ions and negatively charged hydroxide ions (OH-) are equal. Values below 7.0 are acidic, signifying a higher concentration of H+ ions.
Water with a pH above 7.0 is considered basic or alkaline because the concentration of hydroxide ions outweighs that of hydrogen ions. To make water more basic, the goal is to shift this chemical equilibrium by increasing the number of free OH- ions. Adding alkaline substances introduces compounds that either release OH- or react with H+ ions, effectively raising the pH level.
Simple Home Methods for Increasing Alkalinity
One of the most accessible methods involves using sodium bicarbonate, commonly known as baking soda. When dissolved in water, sodium bicarbonate undergoes a mild alkaline hydrolysis, which produces hydroxide ions and gently raises the water’s pH. Adding a small, measurable amount, such as a fraction of a teaspoon per gallon, can typically raise the pH to a mildly alkaline level, often around 8.0 to 8.4.
Commercially available mineral drops offer a concentrated way to increase alkalinity. These liquids often contain alkaline minerals, such as potassium carbonate, calcium, or magnesium compounds, or sometimes sodium hydroxide. A few drops added to a glass of water can significantly and quickly elevate the pH.
Another simple technique is boiling water, which can result in a minor pH increase. Tap water often contains dissolved carbon dioxide from the air, which forms a weak acid called carbonic acid. Boiling the water drives this dissolved carbon dioxide gas out, removing the acidic component and allowing the pH to rise slightly toward a more neutral or basic level.
Specialized Filtration and Commercial Systems
Water ionizers are countertop or under-sink appliances that use electrolysis to create alkaline water. The machine first filters the water, then passes it over positively and negatively charged electrodes. This electrical charge separates the water into two streams.
The alkaline stream is produced at the negative electrode (cathode), where positively charged alkaline minerals like calcium and magnesium are concentrated, along with a higher presence of hydroxide ions. The acidic components are directed to the positive electrode (anode) and diverted into a separate, acidic stream. This method can produce water with a pH ranging from 8.5 up to 11.0, depending on the machine’s setting.
Remineralization filters are frequently used as a final stage after reverse osmosis (RO) systems. The RO process removes nearly all dissolved solids, which can leave the water slightly acidic. These post-filters contain natural alkaline mineral media, such as calcium carbonate, magnesium oxide, or calcite.
As the purified water flows through the filter media, it dissolves these minerals, adding them back into the water. This process raises the pH to a slightly alkaline range, typically between 7.5 and 9.0, while also improving the water’s taste. Portable alkaline water sachets or sticks function similarly, using media like tourmaline or maifan stones to slowly release alkaline minerals into the water over time.
Monitoring and Safety Guidelines for pH Adjustment
When adjusting water pH, two main tools are available: pH testing strips and digital pH meters. Testing strips provide a quick, general estimate by changing color when dipped in the water, but a digital pH meter offers a more precise numerical reading. Monitoring is essential after adding any compound or installing a new filtration system to ensure the desired level is maintained.
For drinking water, the optimal pH range is generally considered to be between 6.5 and 8.5, although a slightly higher range of 8.0 to 9.5 is often a target for those seeking basic water. The human body is highly regulated, but excessively high alkalinity can cause issues.
Extremely basic water (above pH 9.8 or 10.0) may have an unpleasant bitter or soapy taste. It can lead to gastrointestinal irritation, or in rare cases, metabolic imbalances. Monitoring the water’s pH ensures that the level remains within a safe and desirable range for regular consumption.