The water in Austin really varies from day to day as we've found. For instance, one of our clients is on a well directly tapped into the Edwards Aquifer. About 2 months ago a HUGE piece of earth fell into the aquifer (we're talking football field sized) and stirred up aeons of stuff. At that point, the incoming TDS was 999+ on the meter. To solve the problem we added several prefilters to the system and waited for the whole thing to calm down.
Recently we learned that all DI resin is not created equal with certain formulas targeting certain molecules and different grades existing throughout. Going to a mixture of DI resins that all have a specific purpose really has improved our quality and eliminated strange diatom blooms. Silicate lab tested still came out high until our addition of filter chambers with specific silicate DI. If any of you are still interested in the topic at hand call up at the store and leave a message and I'd be happy to discuss it with you.
Thanks,
John
PS: 0 TDS doesn't mean perfectly clean water