Depends on the design of the test. An itneresting one would be to look at the water energetically such as the homeopathic frequncies that it is carrying as well as the gross polutants. Also its electrical potential and spin angle on the electrons. Also the cluster size and bond angles. These kinds of tests reveal way more important facts about water than any mainstream test ever will. Water carries information much like a computer chip does.
Water is a major medium that carries intent. It is no accident that we are made up of 95% to 98% water.
A good approach to purifying and resseting water is utilizing reverse osmosis, then distilled, then vortexing (with magnetic influence) to reset the energetics of the water (stored information). A glass lined distiller is best as not to add back any unwanted metals to the water. There are lots of options for vortexing. I use a simple spiraling device that attaches on the end of a water bottle and spirals into another water bottle (its' a coupling device). Simple and effective. Tunbing forks at a very specific frequncy can also reset water ( a bit like demagnitzing a tape cassette).
Another great way to get healthy water is from a deep artesian well that flows out of the ground, then flows for a ways (natural eddies..spirals) and is influenced by the sun and then collected. If and only if the water is unpolluted (a rarity these days due to our collective world seeing the world as an unconected/seperate part of us that we can do anything without consequence...thus pollution).
May you find studying water as enjoyable and reavealing as I have.
If you want to do some studies into the intetion holding properties of water I recomend getting a magnetic inducer and a computer program capable of synthesizing accurate freqeuncies and combinations. Also a microphone, so that you can induce a controlled signal into the water via the inducer. You can use dry ice to flash freeze water and a decent microscope will reveal some interesting results.
Emoto has done this in elaborate fashion. I recomend studying his work. Also look into Victor Shauberger's work. This will lead you to more and more interesting places. Good luck. Other areas of study that complement this are homeopathy, energy medicine, fractal reality, attractor programs, etc.
In the end we don't need anything "outside" of ourselves but our own unfiltered intentions to create wellness or illness or any experience. The revelution of consciousness takes place within as we become clear and cohernet (uncumbered by negative, and fragmented, unholistic belief systems).