what are acceptable tds?

[Tony40]

just replaced membrane,carbon,sedimate filters and tds reading at 19-20 what reading is good to use water at?

[Bifferwine]

Under 10 is ideal. If you have an RODI unit, it should be reading less than one. Did you let the water run for a while after changing everything? You should run several gallons through before testing.

At any rate, 19 to 20 isn't bad. It won't hurt anything in your tank, but an RODI unit should be performing better than that. If it's just an RO unit (with no DI), then that may be as low as it gets.

[Tony40]

did order d/i filter assembly but have recieved it as yet thank you very much for your info think i could use this water have it hooked up with new filters less than 3 hrs and has made 4 gals on a 50gpd system

[ccCapt]

Measure the TDS of the water before the filter. You can then figure out what kind of rejection rate your getting. The filtered water should be at least 90-95% less than out of the tap.