Abstract: A fluid level control apparatus for a fluid reservoir and comprising a weatherproof housing having a plurality of micro switches mounted therein, the interior of the housing being in communication with the fluid reservoir, a reciprocal rod member extending between the interior of the housing and the fluid reservoir and operably connected with the micro switches for actuation thereof upon reciprocation of the rod, a diaphragm secured to the reciprocal rod and flexible thereby, a helical spring acting against the diaphragm for providing a preselected constant force thereagainst in one direction, a pair of in-line weight members suspended from the reciprocal rod outboard of the diaphragm and calibrated in relation to the physical characteristics of the fluid and force of the spring for counterbalancing of the spring to maintain the diaphragm in a neutral position during normal fluid level conditions within the fluid reservoir, the combined weights of the weight members being variable upon the fluctuation of the