Copper in water is a common problem in many households. Copper is present due to the corrosion of plumbing materials from Acidic (low pH) or Aggressive water (low TDS). Common problems associated with copper due corrosion are leaks in the plumbing system or blue-green staining. High copper content can also cause some health concerns by effecting the stomach and intestines. The EPA has set a maximum contaminant level of 1.3 ppm.