Even purified water is murderously destructive. Indeed, water is more destructive to materials than many other liquids. And deionized water is the worst. It tu

Even purified water is murderously destructive. Indeed, water is more destructive to materials than many other liquids. And deionized water is the worst. It turns out that you have to explicitly make deionized water for a reason: Many of the things that touch water want to dissolve in it! And the fewer ions of, say, copper that are already in your water, the faster a rod of copper dissolves when you dip it into that water. Think of water the way you think about the blood of the aliens in Aliens – only on a slightly slower timescale – and you'll realize why boat maintenance is better thought of as a lifestyle rather than as a series of repairs.