The optimal average pH for water is 6-8.5, which is close to the natural conditions of the geological rocks where the water is extracted from. If the pH of water is more than 7, which is the neutral pH level, it will affect its taste as it will make it more alkaline.
Therefore, it is important to test the water pH before it can be used for drinking, washing, cleaning, and other uses. We can use a pH kit to measure the pH of water. This includes a pH test meter, pH indicator drops, and pH test strips.
However, we can still determine the pH of an unknown sample solution of water without a special pH kit. The following ways explain how to test pH of water without a kit at home
How to Test pH of Water without a Kit? Top 4 Methods
1- Testing pH using Red Cabbage:
We can use red cabbage to test water pH using the following steps:
- Red cabbage is cut up lengthwise and placed aside
- Boil 2 cups of distilled water and pour it on top of the cabbage so that it is submerged for 30 minutes
- The surrounding water will turn into a purple/red color and will be used as our pH solution that we test
- Once we filter the cabbage out by transferring the purple water into a separate container, put a few drops of pH indicator into the water
- This water will now change in color. It will appear pink/red if it is acidic, remain purple if neutral, or become blue/green/yellow if it is alkaline.
2- Testing pH using Digital pH Meter:
This is the most accurate and error-free way of testing pH. This is because it reduces human error made while reading the pH numbers as it is simply displayed on the screen and one does not need to compare the color of a solution with a color chart.
Adding on, each person does not see color the same, and color may appear different when seen from different angles. Dip the end of the pH meter, which is an electrode, into the solution to be measured and read the value displayed on the screen.
Furthermore, to be sure if we have made an accurate test, check the pH of a known solution, like bottled water, to see if it shows the right value written on the bottle pack. It is best to leave the meter in the solution to adjust and do not affect the real pH.
The digital pH meter can be very simple, or it can come with other equipment such as glass probes and a separate voltage screen which then have to be used accordingly. Some pH meters are waterproof, like Pure-Pro, which works with batteries.
Others require the attachments just mentioned, with only free electrodes touching the sample water solution. (Free electrodes are not built-in with the meter, but they can be removed and attached to the meter when desired).
3- Testing pH using Filters:
For this, we have to test strips and glass tubes as our only equipment, besides the sample solution at least. If a testing strip is not available, we can make our own using an acid-free filter such as a coffee filter.
Cut it up, preferably into rectangles. This acts as a testing strip. We soak the filter with water and then let it try in an acid/alkaline-free environment. After this process, the filter can be used as a testing strip.
First, place the dried coffee filter into a transparent tube. Next, pour some sample water onto the filter with a cotton swab. Lastly, use a color chart to compare the color of the testing strip (dried coffee filter) to determine the pH of the solution.
If we have an available testing strip, simply place the strip into a glass tube and soak it with the sample water to cover it fully. The color will change fairly fast, and the resulting color of the strip can then be cross-checked with a color chart.
4- Testing pH using Litmus Paper:
Litmus paper simply tells us whether a solution is acid or alkaline. Dipping a red litmus paper into a supposed alkaline solution will turn it blue if it is truly alkaline. Similarly, dipping a blue litmus paper into a supposed acid solution will change its color to red. If the solution is neutral it will stay the same color.
A common neutralizing filter can be used to change the pH of the water, once tested, to make it fit for safe and healthy usage.
How Neutralizing Water Filters Work?
These are used for too acidic water, i.e. the pH is well below 7. A neutralizing substance is added to bring the pH level back up to around 7. This makes it less likely for the water to corrode the pipes or create other plumbing problems.
Two substances are used depending on the amount of neutralization required. Firstly, calcium carbonate is used if the pH is more than 6. Secondly, magnesium oxide is used if the pH is below 6.
Unfiltered water is made to flow through the filter bed, dissolving the respected substance and neutralizing the water.
Time, maintenance, and considerations for Neutralizing Filters:
The filters work slowly and neutralize about a maximum of 3 gallons per minute per square foot of filter area.
The water for the filter needs to be refilled and cleaned frequently. A cartridge filter is submerged before the filtration process to remove unwanted particles in the water.
Neutralizing water filters are likely to make the water “hard” as the substances dissolve in it. To prevent this, or reduce it at least, a water softener is used.
The pH of water needs to be checked for it to be fit for consumption. The ways mentioned above describe the various methods, which are simple and do not require fancy equipment or kits. After pH is tested, a neutralizing filter can help bring the pH to the optimal value by neutralizing the solution as explained already.