Reduce colour and improve water taste & appearance Filpumps colour reduction systems remove high levels of natural tannins from your water and are often used in conjunction with other Filpumps water treatment systems to provide a total water solution. Filpumps can help you chose the best system for your water. Effects of colour Water can be coloured by humic and fulvic materials from peat or other natural decaying matter (often known as tannins). This natural colour is more common in surface waters (burns and streams) and often worse in spring and autumn when leaves and other vegetation is abundant. The tannins give the water a characteristic brown tint. The UK water quality regulations specify a standard of no higher than 20 mg/l Pt-Co. How does it work? Common methods of removing colour are ion exchange resins or granular activated carbon (GAC). With ion exchange resins the water passes down through a mixture of colour removal resins where the colour is held. When no more colour can be held the resin needs regenerating by backwashing with a concentrated solution of salt (brine). The trapped tannins go down the drain. The resin bed is then rinsed with clean water and returned to service.