<prompt> Hardness of water is due to all except:SulfatesChloridesNitratesPhosphates  <response>: Hardness of water Temporary hardness carbonate hardness is due to calcium magnesium salts of bicarbonates. Permanent hardness non - carbonate hardness is due to calcium magnesium salts of sulfates, chlorides, nitrates. Four main compounds causing hardness: calcium bicarbonates, magnesium bicarbonates, calcium sulfates, magnesium sulfates. 