TDS Calibration

[Cibo]

Not sure if my RO is working I think I need to calibrate my TDS what type of water can i use for this, will distilled water work or just regular bottled water that I can buy?
I get a reading of .24 from a bottle of poland spring 1PT bottle, this leads me to believe that it is out of calabration

thank you

 

[nanoreefer22]

That sounds right for poland spring.

 

[Cibo]

is that what you get from bottle water

 

[nanoreefer22]

Just about

 

[Cibo]

so it should b working ok than