The first step in delving deeper into the water you are using is to increase the quality of the testing. There are a plethora of testing devices available to measure the different values of any given water.
The PH of the water determines how acidic or alkaline the water is. Coffee itself is a mildly acidic beverage at around 5.5. A PH of 7 is neutral. Interestingly, a neutral or slightly alkaline water is preferable for brewing coffee.
Measuring the PH of your water allows you to understand the impact it may have on flavour – a more acidic water will actually produce a slightly less acidic brew and vice versa. It will also allow you to combine the reading with a few other key metrics to utilise the Langlier Saturation Index to understand the impact the water you are using could have on your coffee equipment.
There are many types of PH meters. With all devices it is essential they are regularly calibrated ensure accurate and consistenet results.