How to Remove Manganese From Water (2024)

Key Takeaways

Elevated levels of manganese in well water, more common in the eastern US than the west, can stain fixtures and, in rare cases, pose a health risk.

Signs of high manganese include dark or rusty stains on household fixtures or laundry and, potentially, a foul or metallic taste to your water.

Several common types of home filtration can easily remove manganese from your well water, including reverse osmosis, air injection oxidation, and ion exchange.

To ensure the quality and safety of your drinking water, consider using Tap Score’s water testing kits.

Manganese Removal Methods

Once you confirm that the culprit behind the metallic taste and brown color is manganese, it’s time to remove it from your water using a reliable treatment method.

Since manganese and iron are usually present together, you should invest in a system that can treat both of these dissolved metals simultaneously.

Luckily, several purification technologies can achieve this.

Reverse osmosis (RO)

Reverse osmosis can remove almost 90% of the manganese and iron in your contaminated water supply. From bacteria and viruses to metallic and organic pollutants, the RO filter membrane can remove particles as small as 0.001 microns.

It works by pushing water through a very fine semipermeable membrane that captures the contaminants and washes them away.

Many RO filters can be attached with a combination of other filters, like activated carbon and sediment filters, to treat water down to the last pollutant.

Depending on the quality, the filtration membranes must be replaced every one to two years, sometimes sooner for heavily contaminated water.

You’ll find RO systems in the price range of $250–$4,000, depending on the size and design of the unit.

So, if you have more than one contaminant, take my advice and go for a good-quality RO system. Trust me, it’ll pay off greatly in the long run.

Here’s a list of the best tankless reverse osmosis systems.

Oxidation

The most common methods of iron and manganese removal involve oxidizing them with a strong oxidant to form solid particles, which can later be filtered out through mechanical filtration.

You’ll find a variety of purification systems that use air, chlorine, ozone, or potassium permanganate as oxidants to pretreat manganese and iron.

Air injection oxidation (AIO)

AIO filters work by oxidizing metallic ions in water in an air pocket just above the tank. This water then passes through a filter media (such as greensand, explained below) that captures the solid oxidized particles.

Such filters require periodic backwashing to flush the captured pollutants into the drain.

Nowadays, high-quality filters come with automatic backwash and regeneration operations that you can control through your smartphone from anywhere around the house.

AIO filtration systems are available within the range of $200–$1,500.

Check out our review of the SpringWell WS1 Whole House Filtration System and learn more about air injection oxidation.

Chemical injection of chlorine and potassium permanganate

Chlorine and potassium permanganate are also oxidizers that can turn invisible, dissolved manganese into solid particles removeable by activated carbon.

Chlorine oxidation offers the additional benefit of killing microbial contamination in water.

Chemical injection systems cost around $300–$1,000.

Greensand

Greensand filters are a great way of trapping soluble iron and manganese pollutants in water. They’re made from glauconite coated in manganese oxide.

How it works is that the manganese reacts with the greensand to form solid particles that subsequently become trapped in the greensand.

The good thing about using greensand for oxidation filtration is that it oxidizes and filters the metallic ions in one place. You don’t need to attach a sediment filter or other filter separately to trap solid particles.

It also removes iron, hydrogen sulfide, radon, and arsenic, in addition to manganese.

However, one downside is that the filter media requires regular regeneration and backwashing with potassium permanganate. Just keep in mind that potassium permanganate is toxic and must be stored carefully.

You can find a good quality greensand filter for $300–$800.

Ozone filtration

I must preface this section by disclaiming that this is not a common filtration method for homes. It’s expensive and complex, so it’s more likely to be useful in large-capacity situations.

However, because you might see it mentioned on sales websites, I wanted to include it.

Ozone filtration systems use ozone as an oxidant to convert dissolved iron and manganese into solid particles capable of being filtered, just like other oxidizers.

Some filters come with built-in sediment filters, while others require the installation of a separate sediment filter. Certain catalytic-carbon filters also work great with ozone filters to remove manganese and iron.

This type of filtration uses an ozone generator to produce fresh ozone continuously and is slightly expensive, costing you anywhere between $900 and $3,000, or more.

But the good thing about this filter is that it treats bacteria and viruses along with metallic ions.

Ozone injection water treatment is not that common, probably because it comes with serious downsides. In addition to its high cost, it may present high toxicity and carcinogenic risks.

Ion exchange filters

An ion exchange water treatment system uses the principle of replacing metal ions with other more desirable ions (usually sodium) with the same charge.

Your water softener is a prime example of an ion exchange filter.

Although ion exchange is known for its effective removal of the most common hardness-causing minerals — calcium and magnesium — it can also remove iron and manganese from water.

One thing to remember is that the ion exchange process is good for only small amounts of iron and manganese; excessive amounts can quickly clog the system and render your equipment useless.

In addition, if your water has some percentage of solid oxidized metallic ions, it can foul the filter bed. You’ll have to install a sediment filter before the ion-exchange filter to prevent solid particles from entering the water-softener resin bed.

If your well water is infected with iron bacteria, make sure you treat it with chlorine or any other oxidizing agent beforehand.

Once the resin bed reaches its maximum capacity, it must be regenerated and backwashed to flush out the captured metallic ions.

Water softeners can treat up to 5 mg/L of iron and 2 ppm (parts per million) of manganese. An average ion exchange system will cost you around $700, in addition to the ongoing cost of water softener salt for most models.

For more information about water softeners, check out this list of the best water softeners.

Birm filters

The Birm granular filter works on a similar principle except that it doesn’t require regeneration with potassium permanganate.

Instead, such filters use the dissolved oxygen in the water to regenerate themselves.

For Birm to be effective, your water must fulfill certain conditions, such as a pH higher than 6.8 and dissolved oxygen equal to 15% of the dissolved manganese and iron concentrations in water.

Birm filter media will cost you $50–$150.

What Is Manganese?

Manganese is one of the many metallic minerals found naturally on our planet in soil, rocks, groundwater, and surface water.

Unfortunately, human activities, such as mining, steel production, and unmindful waste disposal, also release manganese into the environment in excessive amounts.

According to the basics of chemistry, iron (Fe) and manganese (Mn) are alike in many respects, and they usually, if not always, originate from the same sources. If you have manganese in your well water, there is a high chance you have iron, as well, because they occur together in nature.

One study says that almost 2.6 million private-well owners in the US consume high levels of manganese in their drinking water.

This article from the US Geological Survey includes a map of where manganese appears most heavily.

In deep and old wells, aquifers come in prolonged contact with manganese rocks, which is why private wells are more prone to this contamination.

But this doesn’t mean city water folks never face manganese contamination.

How badly your water is contaminated, whether well or municipal, largely depends on your location and the mineral makeup of the groundwater.

Similar to iron, manganese can appear clear when dissolved in water but when oxidized into solid particles, may appear as brown and black stains on plumbing fixtures.

In some extreme cases, manganese pairs up with materials like tannins in deep wells to form colloidal manganese or black tint.

Is Manganese Dangerous?

Manganese is a vital mineral for your body and is found in many fruits and vegetables.

Although it’s needed in only trace amounts that a balanced diet can easily fulfill, it’s responsible for the normal functioning of the brain, regeneration of tissues, calcium absorption, and regulation of enzymatic activity.

Manganese deficiency is rare, and there are no established studies discussing its repercussions.

But there is solid evidence that high doses of manganese, also called manganese toxicity, can damage your health.

You can easily fulfill the daily requirement of this mineral through your regular diet. That’s why consuming manganese in contaminated water might lead to overconsumption and health problems.

Let’s explore a few ways high manganese in your drinking water might affect your health.

Neurological disorders

Excessive manganese exposure may cause clinical neurodegenerative disorders, such as Parkinson’s.

Manganese toxicity can also develop manganism, which is associated with symptoms such as loss of appetite, insomnia, depression, weakness, body tremors, spasms, and fever.

Cognitive disorders

Studies suggest that taking high doses of magnesium through drinking water for long periods of time can halt the development of the brain in both children and adults.

It can cause memory issues and attention deficit hyperactivity disorder (ADHD). Infants taking in too much manganese may develop learning and behavioral issues as they grow up.

Anemia

Another issue with consistently taking in too much manganese is that it can disturb the absorption of iron in your body and lead to anemia.

Since iron and manganese are structurally similar, their absorptive pathways are also the same. Presence of greater amounts of manganese can inhibit iron absorption in the body.

Conversely, excess iron can hinder manganese absorption in the organs.

Household Problems Caused by Manganese in Water

Manganese can affect your home in a few ways.

Damaged plumbing

Manganese can damage your plumbing components by forming a brown coating that builds up as scale in the pipes, clogging them, slowing down your flow rates, and reducing the efficiency of not only your water system, but your water-using appliances as well.

You may find yourself dealing with manganese scale even at concentrations as low as 0.2 ppm.

Stained fixtures

The brownish-black stains caused by manganese on white porcelain fixtures, utensils, and laundry don’t come off easily with soap. Instead, soap can make the stains even worse.

The presence of this pollutant also gives rise to manganese bacteria that feed off metallic ions and form slime and sludge in toilet rings and sinks.

Reduced water pressure

Manganese scale, like iron scale, may clog pipes, water heaters, water softeners, and pressure tanks, disturbing the water pressure throughout your house.

High household costs

All these problems from manganese in your water supply can be a burden on your household maintenance budget.

Replacing damaged components and appliances can cost you a lot of money. And low water pressure and clogged pipes can increase your water bill.

Safe Manganese Limits Set by the EPA

According to the United States Environmental Protection Agency (EPA), drinking water must not exceed 0.3 ppm of manganese ions.

But here’s the deal about iron and manganese: They start imparting a foul smell and metallic taste and staining your toilets and fixtures even at low concentrations of 0.1 ppm.

So, the EPA has further set a Secondary Maximum Contaminant Level (SMCL) similar to Canada’s “aesthetic objective” that defines the threshold as 0.050 ppm, after which manganese starts affecting the appearance, smell, and taste of water.

How to Test for Manganese in Well Water

The best and only accurate way of finding out what’s lurking in your well or local tap water down to the last contaminant is to get it tested in an accredited laboratory.

A lab will send you detailed reports about the pollutants and their concentration in your sample within a week. Your state probably sponsors at least one of these labs, and the test should not cost more than $100.

You can try to test for manganese at home using well-water testing kits or strips. Don’t rely on testing strips too much though. This technique is only good enough for gaining a general idea of the presence of impurities in the water.

The quality and accuracy of DIY water tests varies, and some may not even test for what you’re looking for. If you want the best, use a laboratory.

Final Thoughts

Manganese is present as a mineral ore in groundwater and can easily seep into your well. Even as little as 0.05 ppm of this pollutant can cause problems for you.

Purification methods like reverse osmosis, chlorination, AIO, and ion exchange can easily remove manganese molecules from your water.

It’s time to bid farewell to this annoying pollutant for good!

Here are several articles to expand your knowledge of well water maintenance and well water treatment in general: