Abstract: A system for solar disinfection of fluid. One most preferred version of the system includes: (a) A UVTC, made of a polyethylene laminate film with an approximately rectangular plan, providing: a. A first compartment, b. A second compartment for holding fluid, with a port to fill and dispense. (b) A Disinfection Monitor Module (“DMM”) located in the first compartment which: a. Includes at least one sensor to measure light (e.g. solar UV) intensity b. Provides at least one user interface including: c. Contains a wireless communication interface d. Operates according to a process that ensures sufficient cumulative exposure of the contained fluid to solar UV to achieve adequate solar disinfection. Alternative embodiments may also include sensors to detect additional characteristics, such as transmittance, turbidity, “combined transmittance,” and/or temperature.