Buffers and RO/DI units

[Justusfish]

thanks for the info. I'll aerate then rather than use chemicals

[midgetwaiter]

If your water is acidic coming out of your RO/DI something is wrong. It should be pure water, aka neutral, aka 7.0.

You don't have to add buffer to the water if you are using it for top off as the majority of the calcium and such dissolved in it would be left behind when it evaporates. Many people do add kalk or other things to top off water but that would be considered dosing / supplementation.