• Tannins

    Tannins are found in water that has flowed through large quantities of decaying vegetation. Tannins are generally found in surface water supplies of lakes, rivers, shallow wells & sometimes deep wells infiltrated by surface water. Tannins are difficult to remove from water. One treatment method may be effective in one area but may be totally ineffective 10 kilometres down the road.

    It is all dependent on the vegetation in a given area. In concentrations higher than 0.5 part per million tannins become visible in the water. High levels of tannins will conflict with different water treatment processes.


    Aesthetically displeasing yellow-brown water, yellow staining on toilet fixtures, yellow staining on laundry, imparts a taste and odour. Fish, swampy or musty odours.

    Health effects

    There are no know health effects of drinking water with tannins but because tannins are primarily found in surface waters. Bacteria & parasites can be present. Tannins can harbour bacteria & also flow through many water treatment devices. A point of use or point of entry drinking water system is recommended to improve taste and to ensure safe drinking water.  


    Low levels of Tannins can be treated using carbon filters. Medium levels of Tannins are treated using an OCF filter-(Organic Colour Filter). High levels of Tannins are treated using a Chlorination System followed by filtration.