RO/DI

[youngtimothy]

changed out my filters tonight and I'm back to 0 tds !!!! just a friendly reminder to check and/or change your filters!!!!

[AZDesertRat]

Keep in mind the prefilter and carbon block have very little to absolutely no effect on final TDS, they are there to protect the RO membrane. TDS is removed mostly by the membrane,90 to 98%, and the rest by the DI resin.

Prefilters and carbons should be changed every 6 months and the system disinfected at that time to reduce the possibility of bacteria and virus growth due to dirty housings. The RO membrane should last 18 to 36 months if you use middle of the road replacement filters and 3+ years if you use high quality replacements. Its worth pricing better replacement filters compared to the lower end ones many units come with. Extending the RO membrane life out several years may be cheaper in the long run compared to lower cost replacements in higher micron ratings.

DI resin is usually where the TDS is breaking through. Many do not realize it but DI begins to release weakly ionized substances even before it is exhausted. A few of these substances are all forms of ammonia including nitrates as well as silicates and phosphates. Don't wait too long to replace DI.

We need to get in the habit of testing the TDS at several places, tap water, RO only and final effluent or RO/DI to ensure our systems are working at their peak.

[ReeferRob]

Very informative!