Spear Water and Bore Water Colour and Odour Removal Systems, from Global Water Solutions. Most discolouration and odours are caused by the presence of organic matter and chlorine. The vast majority of these can be removed with activated carbon. These units are used to remove tannin (the yellow colouring you may see in spear water) and the pungent odour often found coming from spears or bores. The process leaves the water crystal clear and odour free. The unit uses a specialised media, which absorbs organic material and dissolved contaminants. Water passing through this particular system is not recommended for human consumption(non potable).