ppm of tap water - whats tolerable?

[Mississippi Steve]

It really depends on the contents of the water more than the actual TDS levels; however, I would say the 250-300PPM area for tops. I have used it higher (400PPM) with no problems though, so...

I am still trying to figure out PPM of what?? Chlorine?? Bromine?? Sodium Chloride?? Fecal Solids?? what?? I don't understand "TDS levels".