What causes stains on sinks or plumbing fixtures?

Tap water may interact with the different metals used in home plumbing systems and produce colorful results. While the stains may be bothersome, your water will usually still be safe to drink and use. Regular cleaning with common household cleaners can control stains on sinks or plumbing fixtures. Stains and their causes include: • These stains are most often noticed along with brownish water. They are found in homes of any age, although they are most common in older homes with galvanized pipe. Reddish brown stains may indicate rust forming in the pipes. • These stains are due to copper in the water from copper plumbing. Typically this occurs in homes less than 2 years old. This problem gradually clears up on its own. ... more