What is Terminox?

What is Terminox technology all about? How does TerminoxISM™ work to filter well water contaminants? Such as iron, sulfur, manganese, dirt, turbidity, foul smells and tastes? As well as the fact it is salt free, chemical free and maintenance free?

Terminox Iron Water Filter Image Image

What is Terminox?

TerminoxISM™ includes an oxidizing mineral, like a rock, that comes out of the ground. It NATURALLY oxidizes things such as iron, sulfur and manganese. It is almost like it is hitting it with air or an oxidizing agent. Except that it is entirely natural. It turns oxidized items into a sediment form which can not pass through its dense mineral bed.

Unlike birm filters which require air injection and much higher minimum pH ranges. Or other filters which require chlorine, salt or hazardous chemicals such as potassium permanganate. TerminoxISM™ is environmentally friendly. And requires no additives at all. It periodically cleans itself in the middle of the night, or whenever you want it to. And requires virtually no maintenance. You just “Set it and forget it”. It removes iron, sulfur, manganese, dirt, sediment, turbidity and harsh chemicals such as chlorine.

As the mineral is a catalyst, it virtually never requires removal and replacement when properly applied. The average Terminox filter should last you 25 to 35 years. It is state of the art Technology that is offered exclusively by WFOA™.

TerminoxISM™ is the ONLY choice

When searching for a back washing iron filter, you have many choices. The TerminoxISM™ filter is a custom built media bed filter with several different types of media to address your particular water. In addition to filtering iron, sulfur, and manganese the Terminox can also filter out sediment.  As the TerminoxISM™ is a custom made filter. The content in the mineral bed can vary a great deal. So it is not a “one size fits all” filter like almost all other filters are. We think all wells are unique. We see wells literally 50 feet apart that are entirely different. That is why you should never treat you well water a certain way. Just because the neighbor did it that way.

What does oxidize mean?

Any good quality and current iron filter technology on the market works under the same basic principal. They turn the iron that is dissolved in your water into a solid. Often using air, chemicals or other methods. This is called oxidizing. And then trap the oxidized iron in the media bed and remove the iron in the back wash. The main benefits of the TerminoxISM™ is that it naturally oxidizes. So it requires no salt, air injection or chemicals to function. And it is “Hard Programmed”.

What is "hard programming"

This advanced technology keeps the unit programmed when you have a power failure. No need for finicky back up batteries that last a few hours either. Our advanced technology will keep this unit programmed for days, weeks or even years. When the power comes back on. The new TerminoxISM™ unit is ready to go. That is why it is also great for vacation homes, hunting cabins and areas with frequent storms and power failures. And even with no power at all. The filter unit will continue to clean your water for an ample amount of time.

NSF Certified Components

TerminoxISM™ is a naturally mined and processed ore. And that ore is certified by NSF for drinking water standards. It makes the water taste so clean and good. All of our tanks and electronic controls are NSF Certified as well for drinking water quality standards.

How is Terminox mineral superior?

Most oxidizing media is of a lower purity (some under 50%). Which is why Terminox  has been a market leader for over 20 years.

Some filters use a coated oxidizing media. Such as Filox, Katalox (zeosorb) or Greensand Plus. These filters use a light manufactured coating of manganese oxide  (under 20% pure in some cases) over silica, or other granular minerals to filter iron and other substances from well water. That means that long term wear and tear on the mineral can remove the oxidizing mineral and render the filter unable to remove all types of iron. The TerminoxISM™ is a SOLID mineral through and through. It is not a coated mineral that can easily dissolve. And that is another reason that it is far more pH resistant.

Coated Minerals are Inferior

While coated oxidizing and manganese based media is somewhat effective initially, solid media will last much longer.  In fact, we’ve had reports of customers who are still using solid TerminoxISM™ media that they purchased over 25 years ago. And once the marginal iron filters lose the oxidizing coating, the dealer that sold it to you makes a fortune on rebidding service calls.  An average coated media bed will last about 3-5 years on average before the coating starts to wear off. And the media needs changing. And it will last a shorter period of time with other certain water issues. Such as low pH, improper flow rate going to the unit, concentrations of both iron and heavy manganese and a number of other reasons.

And then there are solid manganese oxide based well water filters such as Pyrolox. Once popular, one the years Pyrolox began to lose its popularity. Mostly because the overnight pop up companies selling them did not know how to properly size them. And Pyrolox based filters have some ongoing dependability issues when compared with advanced technology such as TerminoxISM™.


Other companies take Pyrolox and put their name on it. Such as Catalox. As the originators of Pyrolox Filters online, we certainly know them better than anyone. While they were a good entry level filter many years ago before something better came along, they definitely have some big drawbacks. Over time they lose minerals due to the loss of "Fines". Upwards fo 2% a year is lost. If the mineral starts packing down from organics or iron bacteria, it can lose even more. The average life expectancy of TerminoxISM™ is 25 to 35 years when properly applied.

Our experience is that Pyrolox filters generally have to be re-bed after 3-5 years as they tend to pack down and become iron bound. Catalox filters are simply Pyrolox Filters where the company has apparently just used a different name so no one would realize that it is the old Pyro Technology. And you should be particularly wary of Pyrolox Filters with Vortec filter tanks. Over time the abrasiveness of the mineral tend to damage those type of filter tanks. The Vortec fad is over.

Is knowing your flow rate that important?

Absolutely. It is essential. We are one of the only companies that will ask you to do a proper flow rate to size your new filter. And it is normally quite easy to do. But it is critical for long term success. If any company does not ask you for a flow rate. Or if they fail to do one themselves. They simply can not be certain they have the right filter size. They are most likely selling a coated media bed filter.

The common result is the need for expensive mineral replacement and service calls. And many of these companies will tell you that it is the fault of your well water and try to sell you more expensive equipment.

Because  back washing requires lifting and fluffing the media bed from the bottom up, heavier media requires a higher backwash flow rate. The important thing in any well water filer application is to get the flow rate right.

Premium grade solid media weighs about 120-140 lbs per cubic foot. While some of the marginal coated media weighs about 60-80 lbs per cubic foot. There is no way the flow rates and sizes can be the same for both. Remember that no flow rate means it is foolish to purchase.


Iron bacteria in well water can cause problems in any well water filter. Because if iron bacteria is present. It can coat the mineral inside your filter with iron bacteria slime. Rendering the filter unable to oxidize clear water iron and eventually become bound with red water iron. And TerminoxISM™ is very resistant to moderate amounts of iron bacteria.

More resistant than any other filter mineral available. But for large amounts of iron bacteria in a well. We recommend a chlorine injection system before a Terminox filter to kill any iron bacteria that may be present. Another great benefit of a TerminoxISM™ filter will also remove the chlorine. So you will have no chlorine in your home or septic system. And with no expensive and messy carbons or cartridge filters to replace. It does it naturally. It makes the TerminoxISM™ choice, the easy choice.

  • Color: black
  • Bulk Density: 125 lbs./cu. ft.
  • Mesh Size: 8 x 20
  • Effective Size: 0.51 mm
  • Uniform Coefficient: 1.7
  • Specific Gravity: 3.8
What is Terminox?