And it's all actually dependent on other factors such as temperature right? I thought I had read somewhere that a solution at 65F will give one reading, and the exact same solution at 75F will give a different reading.
The 200ppm for our tap water was actually rounded up a bit...I like working with even numbers, lol
. The pH of the water straight out of the tap is rather on the high end (around 8) and chlorine content in the water out of the tap is very low. We have a RainSoft water purifier on the house. Don't know how that might affect the ppm reading and what not. It's obviously supposed to make the water "better" by human standards, but I can imagine it wouldn't necessarily be quite as good for plants since water is typically "softened" by removing minerals and such from the water that plants would probably enjoy.