Indoor TDS calibration solution

[turtle360]

I have a real interesting question. Calibration solution for HDM tds meters comes in 342 and 1000 ppm. Which one do we want to use? (I'll put a thing here to spice up the post) :dunno:
Or are we mixing up a batch of salt water?

 

[pop22]

technocally, your suppose to use both, to csalibrate both the high and low end of the range. Using just the 1000ppm works just fine though.