What is a birm filter?
The word BIRM is an acronym for Backwashable Iron Removal Media. The media birm is a manganese-coated aluminium silicate, used primarily for the removal of dissolved ferrous iron in a water supply. It is worth noting at this point that a birm filter will not work if the pH is below 7, as the iron will not drop out of solution. To change the water-soluble ferrous iron to an insoluble ferric iron, an oxidising agent or oxygen is introduced to the system which then enables the birm to remove the iron from the water.
