Rain Water

[strawman]

Can anyone tell me the TDS of rain water

[Carol_Roberts]

It will vary from place to place and day to day. TDS measures what is disolved in the water. Areas with lots of pollution will have a higher tds in the rainwater.

[strawman]

Thanks for the response Carol, guess I'll stick with the R/O

[BigDaddy]

If you have an r/o unit, why don't you own a TDS meter? Measuring the TDS of your R/O water is the only real way of knowing when it is time to change your membrane/resin.