Question: what is the difference between type1 and type 2 deionized water?
Answer: The deionized water that Hach sells is Type 2. Type 1 water is ultrapure water required for critical laboratory applications (Resisitivity >18 MΩ·cm). ... Type 2 water is used in general laboratory applications - it's pure, but not ultrapure (Resistivity > 1 MΩ·cm).