I, personally got this because I have a hydroponics system in my garden and need to know the PH level to make sure the plants are getting the right amount but not too much. To use this meter, you get a sample of the water, turn the meter on, and place it in the water. It will tell what the PH level of the water is. It comes with a few buffers to use to help get the PH level where it should be. You would just add the one you needed to depending on what the meter says.
You can get this item here on Amazon.
I received this item for free or at a discount for my honest review.
Have a great day!