Hello!
I have a few questions:
Where in Canada can I get a home water quality tester kit?
Where can I get ideas for a good science fair project using Arduino?
What are MicroSiemens?
What are MicroSiemens/cm?
How can MicroSiemens determine the TDS (total dissolved solids) in water?
How can MicroSiemens determine the mg/L of the TDS?
More to come.
Thanks!
1 ppm TDS = 1.56 microS/cm.
I thought "MicroSiemens" must be a microprocessor so that shows how seriously you must take this post 
You probably need to define what you mean by good quality water then find equipment that measures what you consider important. Water can contain disolved solids, disolved gases, suspended solids, organic chemicals, bacteria and so on.
Where your water comes from will determine what the main quality issues are. For example water from a deep bore may be low in bacteria but high in disolved solids and gases. Lake or river water will probably have more bacterial contamination and suspended solids. Once you know the problems get a kit that targets those issues as no kit will cover everything.
I don't really see how disolved solids can be measured without boiling/evaporating a sample and then alalysing and weighing the residue - how do kits measure this?
You can get Arsenic (As) in ground water, which is poisonous. It can also contain Radium (Ra) which is radiactive.
Some bottled water contains Strontium (Sr) which the body uses like Calcium (Ca). Strontium seems to be considered harmless to health and even beneficial for bone conditions. However some artificail isotopes of Strontium such as 90Sr are harmful radiactive products of nuclear fission. Strontium 90 has a half-life of 29years.
Water may contain organic chemicals, sometimes from industrial processes or products. Some of these chemicals mimic hormones such as oestrogen and have been blamed for affecting the sexual development of fish.
Biological contaminants can be a hazard and even boiling may not eliminate them.
So now you have a perfect excuse to stick with alcohol ]