Fluid timer

A fluid timer configured to receive fluid therein when the timer is in a first orientation and to emit fluid along a timer vertical axis during pre-determined time when the timer is in a second, reversed orientation. The timer comprises an outer vessel having an outer vessel interior extending between its top and bottom along the axis, and is configured for holding fluid within the outer vessel interior in the first orientation of the timer. The timer further comprises an inner vessel at least partially disposed within and surrounded by the outer vessel interior. The inner vessel has an inner vessel interior extending between its top and bottom along the axis, and is formed with one or more ingress ports closer to its bottom than to its top. By these ingress ports the outer and inner vessels are configured to function as communicating vessels to allow filling of the inner vessel with fluid, in the first orientation of the timer, by allowing fluid from the outer vessel to enter the inner vessel through the ingress ports. The inner vessel is further formed with at least one egress port configured to allow the fluid to be emitted therethrough from the inner vessel interior during the pre-determined time, when the timer is in the second orientation.