Identify what type of iron you're dealing with
Iron bacteria look like iron but require different treatment. A lab test for iron speciation plus bacterial culture rules in or out iron bacteria — saves you from buying the wrong filter for the wrong problem.
Order Iron Speciation Test (~$130) →Iron bacteria are microorganisms that feed on iron, manganese, and sulfur in groundwater. They're not a health threat (unlike coliform bacteria) but they cause slimy, reddish-brown deposits and can make water smell terrible.
Signs of iron bacteria
- Reddish-brown or yellowish slimy deposits in toilet tank
- Slimy film on the inside of plumbing fixtures
- Oily-looking sheen on standing water
- Musty, swampy, or rotten odor that's different from simple sulfur smell
- Reddish-brown staining similar to regular iron — but with a slimy texture
How iron bacteria get into wells
- Present in soil and surface water that infiltrates the well
- Introduced during well drilling, repair, or pump work
- Migrate from other parts of the aquifer
- Thrive in wells with iron-rich water and low oxygen — ideal conditions for many private wells
Why standard iron filters aren't enough
A standard air injection iron filter (like the Springwell WF1) oxidizes dissolved iron but doesn't reliably eliminate iron bacteria colonies. The bacteria can survive in the filter media itself and recolonize the water supply. Treatment requires a combination approach.
Treatment for iron bacteria
- Shock chlorination — initial treatment. Disinfects the well and removes existing bacterial colonies. A temporary fix that must be combined with ongoing prevention.
- Continuous chlorination + carbon filter — a chemical dosing pump injects small amounts of chlorine into the water line. Most effective ongoing treatment for iron bacteria. A carbon filter downstream removes chlorine taste and odor before use.
- UV disinfection — kills bacteria before they reach your fixtures, but doesn't address the bacterial biofilm already in the well. Combine with shock chlorination.
- Peroxide injection — hydrogen peroxide injection oxidizes iron AND kills bacteria without the chlorine taste concerns. More expensive but highly effective.
After treatment — protecting your softener resin
If iron bacteria have been running through a water softener, the resin bed may be colonized. After treating the water source, run a resin cleaner specifically designed for iron bacteria removal through the softener. In severe cases, resin replacement may be necessary.