I agree, but how do I get around the Zero Buffer (Kh) of straight RODI water? Or even can I?

I have been using Seachem's Acid Buffer with this Hard water while deciding/waiting on this RO unit. Acid Buffer lowers pH it converts carbonate alkalinity (KH) into available CO2. So, it will steadily eat away at whatever KH I do have--I don't know that that's a Good thing. In theory I guess, I could continuely add more KH with Baking Soda or Seachem's Alkaline Buffer. Seems like I could work out some kind of receipe to reach the goal.