An apparatus for the treatment of a liquid comprising includes a chamber having at least one inner surface. The chamber is at least 80 percent enclosed. The apparatus also includes an ultraviolet (UV) transmissive tube and the UV transmissive tube disposed within the chamber and adapted for the passage of the liquid therethrough. The apparatus further includes an UV lamp and the UV lamp being disposed within the UV transmissive tube. A reflective material is interspersed between the chamber and the transmissive tube, and the reflective material is adapted so as to reflect at least a portion of light emitted by the UV lamp. Additionally, the reflective material is at least 80 percent reflective.