View Full Version : What are all of the things that I should test my RODI water for to make sure its pure

John Hartford
06/17/2006, 08:00 PM
I was wondering what are the "things" that I should be checking my RODI water for to make sure its pure, and secondly what equipment or test kits do I need to test the water to make sure its pure, and third what equipment do you use or recommend that you use to test your RODI water with and where did you buy it? So far I only heard that I need a TDS meter, forogt what its suppose to test for though?

06/17/2006, 08:12 PM
A handheld TDS or conductivity meter is the best thing you can get for testing RO/DI water.

06/17/2006, 08:13 PM
TDS = Total Dissolved Solids; a rough estimate of water quality, but doesn't tell you anything about what is actually dissolved in the water

John Hartford
06/17/2006, 08:14 PM
But what do I test for with the TDS meter, and what should the readings be?

06/17/2006, 08:15 PM
TDS should be as close to 0 as possible.

06/17/2006, 10:02 PM
If tds are 0, what could still be in the water that could still be potentially harmful?

06/17/2006, 10:06 PM
if your TDS is reading 0 then all you have is pure hydrogen and oxygen

06/17/2006, 10:18 PM
Well that makes me feel good. So nothing else could be present?

How bout a way to calibrate a TDS meter? Is distilled H2O the preferred method?

06/18/2006, 07:24 AM
They make TDS calibration solutions, depending on the brand of meter you have. A Hanna TDS1, for example, uses a 1 point calibration of 800ppm. It should be explained in the instruction manual of your meter.

06/18/2006, 07:28 AM
Hmm wouldn't it be possible to still have bacteria in the water which the TDS meter would not measure such as spores etc?

06/18/2006, 07:31 AM
Yes, as bacteria / viruses / algae are not dissolved in water.