RO system

[FishHick]

We recently installed an RO system. I purchased a TDS meter and the RO water reads 7ppm. It shows distilled water as 4ppm. Shouldnt the distilled read 0ppm? And is 7ppm good?

 

[kau_cinta_ku]

distilled is not really 0ppm. rodi water is 0ppm. 7ppm isn't bad but IMO i would spend an extra 30.00 and add on a di system.