The JBL ProAqua Test SiO2 Silikate is designed for measuring and routinely controlling the silicate content in saltwaterand freshwater within the range of 0.2 - >6 mg/l. The compensation method developed specially by JBL allows precise and reliable results to be obtained even in moderately discoloured aquarium water e.g. caused by peat filters and disease treatment. Any possible interference due to the presence of phosphates in the water sample are eliminated by the delayed addition of reagent 2.Silicon is one of the most common elements in the world. As a result of weathering of silicate rocks, silicon is washed into surface and ground water in the form of silicate. Depending on the composition of the rocks in a particular area, the mains water will contain up to 40 mg/l and, on rare occasions, even more. Silicate is non-toxic and there is no threshold set in the regulations governing the aquality of drinking water.The significance of silicon for aquariums is as a nutrient for algae (