Inline TDS Meters

[Chaz D]

I've always used a TDS meter after my DI to gauge when it needs changed (looking for 0). I recently heard from someone else that it is better to have the TDS meter AFTER the RO membrane and before the DI to better gauge the health of the RO membrane. The idea that although DI is important, the RO membrane is more important. How is everyone running theirs?

 

[dwest]

I've always used a TDS meter after my DI to gauge when it needs changed (looking for 0). I recently heard from someone else that it is better to have the TDS meter AFTER the RO membrane and before the DI to better gauge the health of the RO membrane. The idea that although DI is important, the RO membrane is more important. How is everyone running theirs?

I have one 2 way inline tds meter that reads before and after the ro unit and another one after each of my 2 DI filters. I can’t imagine running that system without them. Mine came standard with my 5 stage spectrapure system. I also use a hand held to verify.

 

[JoshH]

I have one 2 way inline tds meter that reads before and after the ro unit and another one after each of my 2 DI filters. I can’t imagine running that system without them. Mine came standard with my 5 stage spectrapure system. I also use a hand held to verify.

Run mine the exact same way. Just as important to gauge the health of the membrane as it is to know how pure the water is coming out of your system

 

[Shaummy]

It's both really...I have a dual inline TDS meter on my BRS RO/DI 5 stage, and it measures after the RO membrane, and the other measures post DI.

In the ultimate setup I would have one at the source, after the RO, and and a final one after DI, but I only have the two places to measure, so those are the ones I chose. To me, as long as I'm seeing fairly low TDS out of my RO membrane, I'm not too concerned if I am getting the proper 98% rejection as advertised. The post-DI is a must to measure so you know when the media is depleted.

 

[Tastee]

I have a 4 stage unit and currently have a 2-way TDS meter on inlet supply and after DI. I am waiting for a second one and once that arrives I will be putting it either side of the RO membrane to monitor performance of the sediment and carbon filters and then the RO membrane. I’m also going to turn on an automated flush cycle after the RO membrane when I fit this (have to do a little surgery on the unit for this so want to do it all in one hit). This will let me change the various cartridges when I need to rather than guessing.