There is described an apparatus for disinfecting a fluid, such as water. The apparatus includes a housing having a fluid inlet for inflow of a fluid to be disinfected, and a fluid outlet for outflow of the fluid to be disinfected. The apparatus further includes one or more light-emitting diodes (LEDs) operable to emit ultraviolet (UV) light for disinfecting the fluid to be disinfected. A fluid flow path extends from the fluid inlet to the fluid outlet. The fluid flow path is configured such that, when the fluid to be disinfected flows along the fluid flow path, the fluid to be disinfected flows sufficiently close to the one or more LEDs so as to absorb heat generated by the one or more LEDs.
