Abstract: The present invention provides an easily mounted, self-contained, compact fluid leak detection kit and/or method. When water begins to flow through the kit housing, a flow switch triggers a timer mechanism such as a processor. As long as the flow continues, the timer mechanism will count down the amount of preset time. The kit provides a manual or computer controlled adjustment to set a predetermined delay time or shutdown time, which is adjustable to the normal operating cycle time of any particular toilet. In this way, the water is shut off as quickly as possible if a leak occurs. The kit may also provide overflow protection, reset to initial values, low battery indication, and bypass function with suitable hardware to implement each.