Re: now explain this, hookahpros. . .
its common with brass, i have green come out of my mya after every smoke when a rinse it out, its just the smoke that sticks to the sides building up a layer of light corrosion but since it mixes with the smoke that sticks it gets the green color very fast. iron/iron alloys (steels) are the only metals that rust, the other ones have corrosion which usually develops a patina and stops corroding where as rust will "grow" into the metal.