Filox works on the principle of a catalyst reaction, but itself remains relatively unchanged. This reaction is accompanied with the formation of intermediate compound or compounds, such as higher oxides of manganese. By alternate composition and decomposition of these oxides, the Filox is left unchanged. Filox works on a principle whereby the hydrogen sulfide, iron, and manganese are actually oxidized in the media and simple backwashing cleans the bed. Filox is very dense and heavy and stops the oxidized solid form of iron, manganese, and hydrogen sulfide from proceeding any further through the media (anything greater than 20 microns). Since the Filox media is so dense and heavy, high backwash rates are required to clean the media. No chemical regeneration is required and nothing is imparted into the drinking water.

Filox is a superior performer because of its very high manganese dioxide content. Manganese dioxide is the active ingredient of all leading iron/manganese reduction systems. Filox consists of 75% to 85% manganese dioxide By contrast, Manganese Greensand is 3% and Birm is 1% manganese dioxide. The high manganese dioxide content produces a much more active and energetic medium—therefore, a much more effective product.