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Problem GuideIron Bacteria

Iron Bacteria in Well Water: How to Identify and Eliminate It

Iron bacteria create a distinctly different problem than dissolved iron. Here's how to tell the difference and what actually works.

What is iron bacteria

Iron bacteria are naturally occurring microorganisms that feed on dissolved iron in well water. Unlike dissolved iron (which just stains things orange), iron bacteria create slimy, reddish-brown deposits that clog pipes, fixtures, and water treatment equipment. The slime is biofilm — a colony of bacteria encased in iron-rich deposits.

Signs of iron bacteria vs dissolved iron

FeatureIron BacteriaDissolved Iron (No Bacteria)
AppearanceSlimy, reddish-brown deposits in toilet tanks, pipesOrange/brown staining but no slime
SmellMusty, swampy, oily odorMetallic, sometimes sulfur smell
Toilet tankSlimy orange/brown coating on wallsOrange staining but not slimy
Water clarityMay have floating particlesClear until exposed to air
TreatmentShock + continuous disinfection OR chemical oxidationAir injection or greensand filter

Why iron bacteria is harder to treat than dissolved iron

Dissolved iron is a chemistry problem — an air injection filter handles it reliably. Iron bacteria is a biology problem. The bacteria form protective biofilm that chemical treatments must penetrate. Simple air injection alone may not be effective for iron bacteria — the bacteria need to be killed, not just oxidized.

Treatment approach for iron bacteria

  1. Shock chlorination: Flush the well with high-concentration chlorine solution to kill bacteria throughout the system. Provides temporary relief — bacteria typically recolonize within weeks to months.
  2. Continuous chlorination: Chlorine dosing pump injects small amounts of bleach ahead of filtration. Kills bacteria on contact, prevents recolonization. Requires carbon filter downstream to remove chlorine before drinking.
  3. Chemical oxidation (peroxide injection): Hydrogen peroxide injection oxidizes both iron and kills iron bacteria. Combined with carbon filtration, this is the most effective long-term treatment.
  4. Air injection + UV: Air injection handles the iron; UV kills bacteria that pass through. Effective combination for moderate iron bacteria issues.

Does the Springwell WF1 handle iron bacteria?

The WF1's air injection oxidation process disrupts iron bacteria by oxidizing the iron they depend on. For mild iron bacteria cases, the WF1 combined with UV treatment downstream is effective. For severe iron bacteria infestations with heavy biofilm, chemical oxidation (peroxide injection) typically provides better results.

Springwell WF1 + UV →

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