New RO/DI system and some odd readings

[litenyaup]

So I have a new ro/di system and found I’m having some weird reading. Please if anyone has experienced this please explain it to me.

So I have tds meters set up at every stage of my system as I wanted to know what each filter was removing. I have found that my influent water has a tds reading of 338. This water is from a well not city. The water after being filtered by 1 and 5 Micron sediment filters, 1 and 5 carbon filters is 350.

My question is why would the tds be higher after being filtered than the water from my well??

The tds after the ro membranes going into di resin is 9. And the product water is 0. My end water is perfect but I’m worried about burning through filters.

Any help or past experience with this would be great! I added some picture for reference.

 

[Opus]

The prefilters (sediment and carbon) do nothing for tds. Their only purpose is to protect the RO membrane. The sediment filter takes out the larger particles in the water and the carbon takes out the chemicals that are harmful. Both can leach out stuff in the water that can raise the tds slightly.

For comparison, the RO membrane is around .0001 micron.

 

[DesertReefT4r]

Yep the first 2 filters do nothing to lower tds, just protect the membrane. Looks like your setup is working pretty well.

 

[litenyaup]

Thank you guys for the responses. So I did find out direct from brs that those filters normally don’t do anything to drop tds and can actually increase it by a few points. My system is working as it should and should not worry. Thanks again for all the info!!