How long can RO/DI water sit

[subie_driver]

How long can RO/Di water sit in a 5 gallon bucket with a tight lid? I'm curious because I can't always get to LFS to get more water so I get 15-20 gallons at a time. Getting an RODI unit for my house won't work for me at this time.

 

[JohnK]

Indefinitely. It may need to be aerated, but that would not be an issue if it's just being used for ATO. Also RODI is like a sponge for Co2 so it's likely to pick some up which will give you a TDS reading, but you can ignore that.