I need to change my coolant in my red car and I was thinking of using distilled water and Waterwetter with no antifreeze. The car is garage kept and I live in a tropical climate. Freezing is not really an issue. The car has an aluminum radiator and Spal fans; so overheating is also not really an issue. I'm just concerned with the coolant having the proper anti-corrosive and lubrication properties. Does anyone have any experience with using distilled water and an additive instead of a 50/50 mix?