FIELD : water and air purification technology.SUBSTANCE : invention relates to water treatment and can be used at AIC, utilities, food, medical, pharmaceutical, electronic and radio engineering industries. Device for treatment of tap water comprises housing 14 with cover 5, cartridge 13, inlet hole connected by flexible tube 4 with divertor 2, having adjustment valve 3, which determines direction of flow of tap water into housing 14 of device. On outer surface of housing 14 there are permanent magnets 11, and inside housing – silicon crystals 12.EFFECT : invention widens the range of technical means for treating tap water.5 cl, 1 dwg