Brown/Black Staining

Staining can be caused by a number of contaminants including iron & manganese.

iron & manganese are commonly found in western north carolina water sources.

symptoms of Iron include:

• ∙ Yellow/red/brown (rust) staining
• ∙ metallic taste/smell
• ∙ Red clay particulate or color to the water
• ∙ red clay buildup in piping

Symptoms of Manganese include:

• ∙ Darker brown/black staining, Typically darker than iron alone
• ∙ Metallic taste

Treatment for iron & manganese:

Iron filters are effective at treating ferric (precipitated) iron and manganic (precipitated) Manganese.
They can be effective at treating ferrous (dissolved) iron and manganous (dissolved) Manganese.
‍
‍water softeners Can Be effective at treating ferrous (dissolved) iron and manganous (dissolved) Manganese.

further reading

Iron and manganese are classified as Secondary "aesthetic" contaminants by the EPA. The recommended limits (0.3ppm and 0.05ppm respectively) are based on the "Staining Point" for each.  most municipalities will treat for iron and manganese to assist with other treatment requirements and minimize maintenance costs on their equipment due to iron and manganese buildup.

While not recognized as health hazards - some individuals, who are particularly sensitive, have reported gastrointestinal upset due to elevated iron levels.

Iron Reducing Bacteria typically referred to as iron bacteria is a non-pathogenic (harmless) slime forming bacteria common whenever iron is present in water. visually, iron bacteria usually looks like slimy deposits or fuzzy filamentous growth and not just brown water or red clay like buildup in pipes. The most common place to observe iron bacteria colonies is the back of the toilet tank.  while bacterial mitigation methods can address iron bacteria, the easiest and most cost-effective option is to remove the iron and the bacteria dies from a lack of a food source.
‍
if hard water deposits are present, Even undetectable levels of iron and manganese can still cause staining.