Nalcool 2000 prevents high percentage ethylene glycol from getting gummy. The oversize radiator is shiny brass inside. One treatment, 1998 and the coolant will last damned near forever. I did a boil test on the thermostat and the engine iron looked like brand new (2016).
I remember one of the last things I did when packing the containers was to fill carboys with 48 cent per gallon Wal-Mart distilled water. SanMar could care less what the 35' containers weighed. Every car trip means ten gallons of distilled water. Mexican Customs opened one gallon and poured some into a palm and smelled it. I told them it was for my BiPAP machine. They abandoned curiosity in under 3 seconds.
Distilled water costs like sin down here. They call it liquido Para Baterias. Often costs a dollar and a half per pint.
I found the old DOW blue antifreeze the least offensive as far as garbage additives. With Nalcool 2000 it is quite a coolant.