Quote Originally Posted by Neal View Post
I wouldn't think it would go bad once mixed.
It does actually. How long it takes depends on the TDS of the water (total dissolved substances) the purer the water the longer it lasts. It also needs to be stored in tightly sealed containers.

RODI/distilled water is best and will give you a few weeks.

Activated carbon filtered water is good, you will get about a week

Most city/well water will give you a few days.