A solar energy water treatment device for minimizing bacteria and other pathogens in treatment water supplied to the device, the device having an inclined metal surface for receiving treatment water via a supply pipe at an upper end of the metal surface for flow downwardly thereon in a thin surface flow, a clear or translucent solar energy transfer panel being spaced above and adjacent to the metal surface whereby solar energy passes to the water on the metal surface, and water collection means at a lower end region of the metal surface after passage thereon, the treatment water flowing at a rate of between 0.1 and 2 litres/m2/min of the metal surface.
