I took a water test that has the following results: (acceptable standard in parenthesis).

Total hardness: 100ppm (<50ppm) Alkalinity: 120ppm (<180ppm) pH: 7 (6.5-8.5) iron: 5+ ppm (<.3ppm)

I'm trying to figure out which filter system would be best to get between Catalytic Carbon or Birm. I can't really find reviews on either, but they both look like they would get the job done.

Catalytic Carbon Centaur catalytic carbon is a specially prepared carbon made by the Calgon corporation, for the removal of hydrogen sulfide and iron from well water, or chloramines from municipal tap water. Makes a great “whole house” filter for general city water use, especially where chloramines are used, and works well with oxidizers like air and chlorine for sulfide or iron removal. This filter costs more than the standard GAC filter above because catalytic carbon is quite expensive.

```Birm Birm is a medium specially prepared for iron removal. It has the ability to oxidize iron, and can remove small amounts of iron without pre-treatment, but it works best following aeration. It is also effective at manganese removal. The pH must be 6.8 or above for birm to work properly.

Note: Birm should not be used on chlorinated systems.```

From the write-ups, it sounds to me like Birm is a better iron remover, but I don't want to just guess at it. The water is coming from a well and tastes like a jar of liquid pennies. We had a previous iron filter that wasn't designed to take out this much iron, but after adding an additional filter after it, it did take out the iron to the point where it wasn't detectable, so I know it can be filtered. That iron filter died... probably because it wasn't designed for this much iron.

Either filter system I get will have an aerator before it to oxidize the iron.

  • Can you test the water in the well? If you have just moved into the dwelling and the water you're testing has been standing in iron pipes/vessels for some time then you may be getting an iron reading that is not representative of the long-term iron level. Dec 24, 2016 at 21:54
  • Check into the maintenance requirements - if I remember right a birm filter gets backwashed periodically, but the filter media lasts a long time, but activated carbon will get used up and have to be replaced.
    – Mark
    Dec 24, 2016 at 23:05
  • 1
    @AndrewMorton if Francis followed the stock instructions for taking a water sample (as provided by most any water testing lab) the tested water is representative of the well, and would have been collected only after running enough water to flush the standing water in the pipes clear. Trust me, nasty wells are out there, I've had experience with a few.
    – Ecnerwal
    Dec 25, 2016 at 4:24

1 Answer 1


I ended up getting something with Iron Rival Light media. After researching a bit, and finding something that I don't remember the name, but it was created in Germany and said to work better than Filox, Birm or Carbon; but it led me to a company selling a filter with this media and it has this write-up:

Iron Rival Light is a revolutionary new light weight iron treatment media that is best described as a cross between Birm and Filox. As such, it shares the best characteristics of both media. Being a coated media and light weight, Iron Rival light is easier to backwash - it requires less flow rate to backwash and it does not need to be done as often as Filox. Yet, the coating and volume of active ingredient (10% manganese dioxide) is much greater than that of Birm, resulting in longer media life and increased performance. Iron Rival Light has a recommended pH level of 6.0 to 9.0 and effectively removes, iron, manganese, and hydrogen sulfide.

After getting it setup, the water is coming out completely clean!

  • It sounds like you have Katalox Light media. Is that correct? How is it working out almost two years later? Dec 14, 2018 at 21:26
  • I sold the place, so I'll never know.
    – Francis
    Dec 17, 2018 at 22:16

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.