Iron and manganese are commonly found in well water and have various aesthetic effects on pipes, fixtures, and appliances.
Here, we’ve discussed the best methods of iron and manganese removal for private wells.
📌 Key Takeaways:
- Iron and manganese are two minerals that are found in rocks and soils across the US.
- Some of the methods of iron and manganese removal include filtration, chemical oxidation, air injection/oxidation, greensand filtration, ion exchange, and potassium permanganate.
- You should remove manganese and iron from water because they clog pipes and appliances, leave brown, orange, or black stains, and give water a metallic taste.
Table of Contents
🔎 What Are Iron And Manganese In Well Water?
Iron and manganese are two common well water contaminants.
Both minerals are abundantly present in the earth’s crust, and often occur in shallow rocks and soils.
When water seeps through the earth into an underground aquifer, it picks up iron and manganese particles along the way. This water is then used to supply a private well.
The levels of iron and manganese in your well water depend on various factors, including your local geology, the positioning of your well, and whether there have been any events (such as flooding) that may have impacted the soils or ground in the region.
❓ How To Know If Your Water Contains Iron And Manganeses
If your well water contains iron and manganese, you’ll probably notice the following things:
- Brown, orange, or black stains on your fixtures and appliances
- Metallic taste in your water
- Red or brown-tinted water, or orange flecks in your water
The best way to know for sure that your water contains iron and manganese, and the quantity of these contaminants, is to test your water.
If you’re on a private well, your local authority may offer you occasional free or discounted water tests.
Or, you may prefer to contact a laboratory of your own choice and send a sample of your water to be tested for iron and manganese.
⚗️ How To Remove Iron And Manganese From Well Water: 6 Best Methods
Here are the best ways to remove both iron and manganese from well water.
1) Air Injection/Oxidation
Air injection/oxidation is one of the most popular methods of iron and manganese removal.
This system uses an air bubble to oxidize the iron and manganese in a water supply. The oxidation process converts the minerals into their ferric (insoluble) form, making them easier to remove.
Water then flows through a media bed, such as birm or manganese greensand, which further oxidizes and traps the insoluble particles, so that the water leaving the system is virtually iron and manganese-free.
Eventually, the media bed will become saturated with iron, manganese, and other impurities (like hydrogen sulfide), and the system will perform a backwash cycle to flush the contaminants away. The oxygen bubble will also be replenished at this time.
- A big benefit of air injection/oxidation is that it’s a chemical-free process, so it doesn’t add anything harmful to your water.
- This type of system allows for rapid oxidation, and water doesn’t need to be held in a special tank while the oxygen takes effect.
- Air injection is highly effective in reducing iron and manganese, targeting iron concentrations up to 20-30 PPM (much more than you’ll find in a typical well water supply) and manganese up to 10 PPM.
- You don’t have to commit to much maintenance because the system backwashes itself, which extends the lifespan of the media to around 7-10 years.
- Air injection systems are expensive, often costing thousands of dollars upfront.
- These systems can’t be used to treat or remove iron bacteria (which may form a layer of slime over the media and affect its contaminant removal abilities).
2) KDF Filter System
If you prefer to use a cartridge-based filtration system for iron and manganese removal, look for a whole house well water system that uses KDF as at least one filter stage.
KDF-85 is the best type of KDF media for removing iron (up to 5 PPM) and manganese.
Ideally, this filter system will also use a sediment filter, which will trap rust particles (ferric iron).
Once the KDF filter cartridges become clogged with iron, manganese, and other impurities, they’ll reach the end of their lifespan and will need to be swapped out with new cartridges.
- Cartridge-based KDF filter systems don’t require regular backwashing, so they don’t waste water.
- Most multi-stage whole home filters for well water pair a KDF cartridge with a sediment filter and an activated carbon filter, targeting other groups of contaminants in your water.
- Installing a cartridge filtration system is typically easier than installing a tank-based oxidation system, and swapping out the filters is quick and easy.
- A cartridge system is the cheapest whole-home method of iron and manganese removal.
- Because KDF cartridges can’t be backwashed, they have shorter lifespans and need to be replaced frequently (about once a year).
- The additional maintenance of a KDF filtration system means its long-term costs are higher.
3) Chemical Oxidation
Chemical oxidation is another tank-based water treatment solution for dissolved iron and manganese removal.
This method uses a chemical oxidizing agent, such as chlorine dioxide or hydrogen peroxide, that is injected into the water supply with a chemical feed pump.
The chlorine oxidizes the iron and manganese, and these chemicals are then removed from the water using a sand filter, which will need to be backwashed occasionally to remove the precipitared contaminants.
A final activated carbon filter media is usually employed to reduce the chemical oxidizing agent to trace levels, ensuring that water is safe to drink.
- Chemical injection systems are highly effective and should reduce up to 8 PPM of iron and manganese.
- Using a chemical to oxidize iron and manganese has the additional benefit of disinfecting water. Chemicals like chlorine can also destroy iron bacteria – something that most other water treatment systems are incapable of removing – which will prevent clogging of the sand filter.
- Chemical oxidation is another low-maintenance treatment for iron and manganese. You just need to make sure that there’s enough chlorine solution and replace the sand filter every 7-10 years.
- Chlorine is affordable and widely available in most stores.
- The oxidation process isn’t instant with chemical oxidation. Water must be stored in a tank for around 20 minutes to allow the chemical to achieve the desired effect.
- Chlorination produces disinfection byproducts when organic matter is present in the water. These cancer-causing chemicals aren’t typically fully removed by the post-filtration media.
4) Greensand Filtration
Greensand filtration media may be used independently (without an oxidizing agent) to reduce soluble manganese and iron from water.
This method of iron & manganese oxidation uses glauconite as an active material, which is typically combined with other materials to form a blackish-green product that has ion exchange properties, making it capable of adsorbing soluble manganese and iron.
When water flows through the filter material, the soluble minerals are pulled into the media. These minerals are then converted into their insoluble forms, and are eventually flushed from the media during backwashing.
- The filter media replenishes itself with automatic backwashing, so you don’t need to worry about changing filter cartridges.
- Greensand filters are often cheaper than other methods because they don’t combine the media with any other oxidizing agent – oxidation occurs in the same location as the filtration.
- This method of filtration is effective enough to remove up to 15 PPM of iron and the majority of insoluble manganese, improving water quality without the addition of chemicals.
- Maintenance takes a little more work for a greensand filter. You’ll need to regenerate the filter media occasionally with a potassium permanganate solution.
- You’ll need to pre-treat the water if the pH is lower than 6.8, since this will reduce the filter’s ability to remove iron and/or manganese.
5) Ion Exchange
If your well water hasn’t been exposed to oxygen and contains only low levels of soluble ferrous iron and manganese, you can use an ion exchange system (such as a water softener) to remove these contaminants.
The ion exchange process involves exchanging unwanted ions with ions that won’t have aesthetic effects in a water supply. A water softener exchanges calcium and magnesium minerals with sodium or potassium ions.
Ion exchange water softeners can also reduce low levels of dissolved iron and manganese (typically up to 3 PPM). You’ll need to top up the sodium tank with salt or potassium chloride to keep the system running effectively.
You should only use a water softener for iron and manganese removal if you have low levels of these minerals in your water. Excessive iron could foul the resin of the softener, disrupting its softening abilities and shortening its lifespan.
👨🔧 Interested in a water softener that’s capable of manganese and iron removal? Click here to explore our top recommended products in the best water softeners for well water guide
- Ion exchange tackles water hardness and low iron and manganese concentrations, so it’s a great two-in-one solution for hard well water with excess minerals.
- A water softening system backwashes itself, so you don’t need to worry about replacing the resin frequently.
- This treatment method is chemical-free, and only adds natural additives (sodium or potassium) to your water supply, which won’t be detrimental to drinking water quality.
- Too much iron or manganese will foul the softening resin, which will affect its performance and lifespan.
- Even if your water only contains low levels of manganese and iron, you’ll still likely have to clean the ion exchange resin frequently with a rust remover.
6) Potassium Permanganate
Potassium permanganate is another chemical that’s used for manganese and iron oxidation.
This inorganic compound is made from potassium hydroxide and manganese oxide ore, and effectively oxidizes both iron and manganese, ready for removal (typically with manganese greensand media).
You can use potassium permanganate to reduce up to 10 PPM of dissolved iron and manganese.
- The combination of potassium permanganate and manganese greensand is ideal for treating iron contaminated water.
- When potassium permanganate is used alongside a manganese greensand filter, the outcome is more effective because the oxidation process can continue in the filter itself.
- As with chlorine injection, the system backwashes itself, extending the filter lifespan and reducing the need for new media.
- Achieving the optimal dose can be tricky. You need enough potassium permanganate to oxidize all of the iron and manganese, too much of this chemical will turn your water pinkish-purple.
- Potassium permanganate isn’t as affordable or widely available as chlorine.
🤔 Why Remove Iron And Manganese From Your Water?
Now you know how to remove iron and manganese from your water, why should you do so?
There are a few reasons:
Iron And Manganese Affect Your Water Taste
The biggest effect of iron and manganese in your water is poor taste and smell.
These contaminants give water a metallic taste that you may find unpleasant. You may also be able to smell iron and manganese in your water while you’re showering or running a bath.
Water containing manganese and iron may also have an unpleasant brownish, orange, or black hue.
Iron And Manganese Stain Surfaces
Manganese and iron in your water will also stain your bathtubs, sinks, shower units, and any other surfaces that it comes into contact with.
You may notice reddish-brown or black marks on your fixtures. Doing the laundry with iron and manganese-contaminated water will also stain your laundry items.
Iron And Manganese May Clog Your Pipes And Appliances
Excess iron and manganese may build up in your pipes, fixtures, and appliances to the point of forming a blockage.
Your appliances and fixtures may be unable to perform as efficiently if they’re clogged with iron or manganese particles, and you’ll probably experience reduced flow and water pressure.
Iron And Manganese May Have Skin & Hair Effects
Iron and manganese may leave deposits on your skin when you shower.
Routinely showering or bathing in iron or manganese-contaminated water may clog your pores and increase breakouts and dry, itchy skin problems.
⚠️ Are Iron And Manganese Dangerous In Well Water?
Low levels of manganese and iron aren’t considered dangerous in well water.
However, consuming these minerals in excess may have health effects – and they’re also known to have damaging aesthetic effects in plumbing systems.
Manganese may cause health effects including problems with attention, memory, and motor skills in adults and children if large amounts are ingested in water over long periods.
Iron doesn’t usually present a health risk in drinking water, unless iron bacteria is present, which tells you that harmful bacteria have entered your well.
Private wells aren’t subject to state or federal drinking water standards, so it’s the responsibility of the well owner to test their water for potentially dangerous contaminants and remove them with a suitable water treatment method.
🔚 Final Word
Now you know the best ways to remove manganese and iron from your well water – your next step is to start shopping.
In our guide to the best well water filtration systems, we’ve recommended the top products using these water treatment methods for manganese and iron removal.