The fastest and cheapest, though not a particularly accurate method is the determination of the pH value of water with the help of special indicators. For this you will need: a test sample of water, and solutions of indicators are litmus and phenolphthalein in any clean transparent containers, for example, laboratory glass cups.
Add the water in the tank with indicators and closely monitor the response, evaluate the obtained solution: what is its color. Remember that the litmus in acidic medium takes red, and phenolphthalein in an alkaline medium crimson. If the addition of water will not lead to color change, its pH value close to neutral, i.e. 7.
We can also use special test strips. Apply one drop of the investigated water, let it fully soak into the paper and quickly compare the resulting color with a standard scale.
A more accurate method is a method using pH meters. These are special devices whose operation is based on the accurate measurement of the electromotive force that occurs when immersion in the test solution and two electrodes, that is, the pH glass electrode and reference electrode". For such a measurement need only yourself pH meter and a special container, for example, the glass Cup, which is filled with the investigated water. Of course, this capacity must be clean (to avoid errors caused by contamination) and of sufficient size to freely fit two electrodes.
In addition to accuracy, pH meters have the advantage that the measurement of the level of the water with their help you can organize in a continuous and automatic mode, without human intervention, which is very important for many large enterprises.