lol, I'm waiting for a response too.

My understanding is that if it's mixed and NOT exposed to air (oxygen?) then you don't lose effectiveness. I plan on pushing RODI water into a sealed five gallon bucket via an aqualift pump, with a route of escape to the sump for the solution. So in a sense the five gallon bucket will become more diluted over time until I replace the Kalk after a week or so.