The Baileys Drain Tracing Dyes are soluble in water and are used to locate the direction of water flow in pipes, drains etc. The best way to use the dye is to dissolve the required amount into about five litres of water and then add into the flow or tank. The dilution rates assume that the dye is being added to clean water, for examle one 8oz jar will provide enough dye for approximately 15,000 litres/3,300 gallons of water. However please note that dirty water will require a greater concentration of dye.