Birm, Greensand, and Pro-OX Iron Filters: A Primer

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Iron water filters remove iron and other contaminants from your water supply. Install them at the point of entry to treat all the water in your home and solve iron-related issues throughout your plumbing system. Iron water filters can remove various types of iron, including red water iron, clear water iron, and hydrogen sulfide, which is responsible for the characteristic “rotten egg smell” in water. Additionally, these filters can also remove manganese, another common contaminant that can cause discoloration and staining.

Comparing Birm vs. Greensand vs. Manganese Oxide for Iron Removal from Well Water

The three most common systems available to remove iron from well water are back-washing iron filters that use one of three different media: Birm, Greensand, and Manganese Oxide (Pro-OX).

These systems are designed for easy installation, and our support team is available to assist you throughout the process.

Iron makes up 5% of the Planet’s crust and is found in well water worldwide. Whenever the amount of iron in your well water is higher than 0.3 Milligrams Per Liter (mg/L), the water can be rusty, reddish, brownish, or even yellow and cause discoloration of fixtures and laundry. Metallic tastes will probably be present, and the water may smell horrible.

Thankfully, you can easily find iron filters that will work great and remove iron. However, it is important to select the best iron filter for the job, and the iron filter should be carefully chosen after a water analysis has been performed.

Test The Water and Find Out the Well Pump Flow Rate First

It is important to analyze the water for pH, general minerals, and bacteria before choosing an iron filter. Besides analyzing the water, find out what your current well pump flow rates are in gallons per minute, so you can know that the iron filter you choose will work with your flow rate.

Birm is a trade name of Clack Corp. The media is manufactured from natural pumice mineral, which is then covered with a very thin layer of manganese dioxide. Birm will only work if there is adequate dissolved oxygen in the water. The oxygen acts as a catalyst to change the dissolved iron into a dense rust particle that the Birm can then remove. The Birm filter media traps iron rust contaminants, and the iron filter removes them during automated backwashing.

Birm does not reliably remove manganese unless the pH exceeds 8.2, making it unsuitable for water with manganese. It also fails in the presence of hydrogen sulfide gas or chlorine.

Most well water contains low levels of dissolved oxygen, so use an air compressor or air injector to boost oxygen and improve filtration performance. Birm filter media will not remove iron when the pH in the well water is under 6.9. While Birm is the lowest-cost filter media, it doesn’t last that long and may need to be changed every few years.

Check out our current sales and special offers to get the best deals on iron filters.

Benefits and Applications of Iron Filters

Iron filters offer numerous benefits and applications for homeowners. By removing iron and other contaminants, these filters can:

Eliminate iron stains in sinks, toilets, and other fixtures
Reduce the “rotten egg smell” caused by hydrogen sulfide
Prevent manganese from causing discoloration and staining
Improve the taste and appearance of water
Protect plumbing and appliances from iron-related damage
Increase the effectiveness of water softening systems
Provide long-term protection against iron and other contaminants

Iron filters are suitable for various types of water sources, including well water, municipal water, and other types of water supplies. They can be installed in whole-house systems, providing comprehensive protection for the entire home.

Greensand Filters

Just like Birm, Greensand has a thin coating of manganese dioxide. However, Greensand does remove manganese and hydrogen sulfide odors. Greensand filter systems do not use air injection but instead use a purple powder, potassium permanganate, to completely clean and restore the greensand filter media.

An alternative to potassium permanganate can be to inject some chlorine bleach upstream of the Greensand Filter system, which then allows the filter to remove iron bacteria and odors and enable the Greensand Filter to remove virtually all iron and manganese. Well water filters using greensand generally will remove greater levels of iron and work better when compared with Birm. This kind of iron filter works well right down to a pH of 6.5, but works better and lasts longer if the pH is in the range of 6.8 – 7.5.

Greensand’s advantage is that it is lightweight, requires less backwash water, and is lower in cost than solid manganese oxide media filters (see below). However, it needs to be changed every few years and does not last as long as manganese oxide media.

Manganese Oxide Filters: Pro-OX, Pyrolox, Filox, Catalox, and MangOX

Pro-OX, Filox, MangOX, and Pyrolox are all brand names for solid manganese dioxide filter media. We sell the Pro-OX brand, which is a higher-quality and particularly powerful manganese dioxide media.

Manufacturers make these types of media from over 80% pure manganese ore, which is naturally mined, then processed and independently tested and certified by NSF for drinking water use. Thanks to its high purity, suppliers collect and prepare it specifically for water treatment applications.

Unlike Birm and Greensand, Manganese Oxide filters use a solid manganese oxide ore and are, therefore, not coated. Manganese Oxide Filter systems have brand names such as Pro-OX, Pyrolox, Filox, Catalox, MangOX, and others. This particular media will last many years longer than Birm or Greensand.

Because this media is extremely heavy, the system must use a higher water flow to backwash it compared to Birm or Greensand. For best results, inject chlorine bleach upstream of the iron filter to enhance the performance of these well water filtration systems.

A manganese oxide filter system will often work better than the other types of well water filters, as long as there is a sufficiently high backwash flow rate to properly clean the heavy filtration media. Manganese Oxide media can theoretically be utilized down to a pH of 6.2, but work best if the pH is between 6.8 and 7.5. It is the longest-lasting of these iron filter media and can easily last 10 to 15 years. We have some customers who have been using the same manganese oxide media since the early 1990s. In addition to removing iron and manganese, this media will remove other metals such as arsenic under the right conditions.

To work effectively, manganese oxide needs an ORP level above 200, which you can easily measure. Injecting air or adding chlorine or ozone before the iron filter raises the ORP and helps the manganese oxide reliably oxidize contaminants.

Installation and Maintenance of Iron Filters

Installing an iron filter requires access to the main water supply line, and it is recommended to hire a professional for the installation process. The filter should be installed in a location that is easily accessible for maintenance and repairs. Regular maintenance is necessary to ensure the effectiveness of the filter, including occasional refilling with potassium permanganate as a regenerant. It is also important to check the filter’s performance regularly and replace it as needed. By following proper installation and maintenance procedures, homeowners can enjoy the benefits of iron-free water throughout their entire home.

Frequently Asked Questions (FAQs)

1. What is the difference between Birm and Greensand for iron removal?

Birm is a lower-cost media that removes iron but not manganese or odors. Greensand removes iron and manganese and helps eliminate hydrogen sulfide odors when used with potassium permanganate or chlorine.

2. How long do iron filter media types typically last?

Birm and Greensand usually last a few years and require replacement more often. Manganese oxide media like Pro-OX can last 10–15 years or more with proper maintenance.

3. Do I need to inject chlorine or chemicals into these filters?

Yes. Greensand requires potassium permanganate or chlorine to regenerate. Manganese oxide filters work best when chlorine, air, or ozone is injected upstream to oxidize contaminants.

4. What pH level is ideal for iron filters to work effectively?

Greensand and manganese oxide filters perform best at a pH between 6.8 and 7.5. Birm requires a pH of 6.8 or higher to function properly.

5. Which iron filter media works best for high iron levels or additional contaminants like arsenic?

Manganese oxide media (Pro-OX, Filox, MangOX) is the most effective for removing high iron and manganese levels and can also remove arsenic under certain conditions.