Tardigrades can survive 30 years without water.
Why it is true
Tardigrades enter a state of cryptobiosis when they lose 99 percent of their body water. In this state, metabolism practically stops and they can survive extreme temperatures, radiation and vacuum. There is no confirmed record of 30 years, but they can survive several years.
Source: NASA
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Tardigrades can survive decades without water by entering a state called cryptobiosis.