Water filter type
Iron and manganese removal
Oxidation followed by filtration, sized to the form and concentration of iron present. The right configuration depends on a test, because dissolved and bacterial iron need different treatment.
Three kinds of iron, three different answers
Dissolved ferrous iron is invisible in the glass. Water comes out clear, then turns orange after standing as it oxidises in air. This is the most common form on a drilled well and it needs oxidation before it can be filtered.
Oxidised ferric iron is already a particle. The water is discoloured the moment it leaves the tap, and a filter can catch it directly.
Iron bacteria are living organisms that feed on iron and produce a reddish slime in cisterns and toilet tanks. Filtration alone does not resolve this. It needs shock chlorination of the well and often repeated treatment.
Treating the wrong form is the usual reason an iron system disappoints, which is why we ask for a test that distinguishes them.
How the treatment is staged
Oxidation comes first, converting dissolved iron into a particle. That can be done with air injection, with a catalytic media that uses dissolved oxygen already present, or with a chemical feed at higher concentrations.
Filtration follows, catching the oxidised particles in a bed that backwashes them to drain on a schedule.
Manganese behaves similarly but oxidises more slowly and at a higher pH, which is why a system sized only for iron can leave manganese behind and keep staining fixtures black or brown.
What this will not fix
Existing stains stay. Once iron has bonded to a glazed surface or into fabric it needs a reducing cleaner to lift, and the treatment system only stops new staining.
It does not address hardness, lead, nitrates, or bacteria.
If the staining appeared suddenly on municipal water, call the utility before buying equipment. Hydrant flushing and main breaks stir up settled iron and the problem usually clears within days on its own.
What it reduces, and under which standard
Each row names the NSF/ANSI standard the category is tested under. A standard describes what the test covers. It does not mean every unit on the market carries that certification, so check the specific model against its listing before you buy.
| Contaminant | Standard | Note |
|---|---|---|
| Dissolved and oxidised iron | NSF/ANSI 42 | Iron reduction is an aesthetic claim under 42. |
| Manganese | NSF/ANSI 42 |
What it does not do
Every filter has a boundary. These are the things this one will not fix, listed so you can rule it out quickly if your problem is on the list.
- Iron bacteria, which forms slime and needs shock chlorination rather than filtration alone.
- Existing rust stains on fixtures and laundry, which must be cleaned separately.
- Hardness, lead, or nitrates.
When it fits
- Orange or brown staining on sinks, tubs, and laundry
- A well test confirms iron or manganese above the secondary standard
- Water runs clear at first then discolours on standing, which points to dissolved iron
When it does not fit
- The staining is blue-green, which indicates copper and low pH instead
- Iron is present as bacteria, which needs a different first step
- No test has been done yet, because sizing without one usually fails
Space, services, and upkeep
A backwashing tank roughly 1 foot by 5 feet, near a drain.
A drain connection is required. It needs a power outlet within reach. This is not a rental option, because it fixes to the building and stays there.
Replacement interval. Backwash cycles are automatic. Media typically replaced every 5 to 10 years.
Problems this is used for
We recommend this equipment against these confirmed problems. Each page explains how to confirm the problem before spending anything, and when treatment is not warranted.
- Iron and rust staining. Iron dissolved from rock or from corroding pipe.
Property types where this comes up
Common questions
Why is my water clear at the tap then orange in the sink?
That is dissolved ferrous iron. It is invisible while it stays in solution, then oxidises on contact with air and turns into the orange particles you can see. It is the most common form on a drilled well, and it tells us the treatment needs an oxidation stage before the filtration stage. Water that is already discoloured as it leaves the tap is a different form and can be filtered directly.
What is the reddish slime in my toilet cistern?
That is usually iron bacteria, which are living organisms that feed on iron and produce a gelatinous deposit. Filtration alone does not resolve it. The well needs shock chlorination, sometimes repeated, and continuous treatment afterwards where it keeps returning. It is worth identifying early, because an iron filter fitted against bacteria will disappoint and will itself foul.
Will it remove the stains I already have?
No. Iron that has already bonded to a glazed surface or into fabric needs a reducing cleaner made for rust, and the treatment system only prevents new staining. Clean the existing marks after the system is running, otherwise you clean them twice.
Other filter types to compare
If the notes above rule this out, these are the neighbouring options worth reading before you decide.
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