Water… Distilled? Purified? Hose??

Spend the money and buy Evans coolant. Water even with rust inhibitors and such is not the best for the system
This link is from a competitor to Evans but raises some interesting issues.

No-Rosion Products Technical Questions and Answers.


Not to mention that Evans is 100% propylene glycol or a ethylene glycol / propylene glycol mix

Technically you could just run straight rad fluid and save 25.00 per gallon.