The two largest factors to ionized alkaline water neutralizing are exposure to air and light. So let’s break down the shelf life of ionized alkaline water based on storage conditions:


Open glass: If left in an open glass exposed to air and light, ionized alkaline water remains optimal for about 2 hours.


Sealed Opaque Bottle: When stored in a sealed opaque bottle, but with some air in it, ionized water retains its benefits for approximately 2 days. 


Airtight Opaque Bottle: For the longest shelf life, use an airtight opaque container and ensure there is no air in it. In such conditions, ionized alkaline water can last up to 2 weeks.


Keep in mind that factors like initial water quality and storage conditions play a role. So, if you’re aiming for maximum benefits, consuming freshly ionized water whenever possible.