"The PH from your DI resin water could be high
and has basically destroyed your tanks buffering capacity over time."

There is no alk or buffering in RO/DI water, all of it has been removed.
RO/DI units
automatically destroy all your "buffering capacity"



You missed the point. I was pointing out that if the mixed bed resin is
exhausted, not only do you no longer have DI water, but it can be
significantly alkaline or acidic. Therefore the constant addition of
alkaline water which you trust to be pure DI water, and it no longer is,
slowly eats away at the tanks buffering capacity. Once the last of the
buffering salts covert to their basic form, the buffering is gone and the PH
starts creeping up.

I'm sorry but I've seen it happen on a very large scale where a plating tank
was destroyed because the DI water automatic top-off shifted the PH of the
tank.

Robert