An electric diaphragm pump having a pump head assembly in a first housing, a motor assembly in a second housing, a fluid sensor, and a leak alert system and/or pump shut-off system. The fluid sensor detects a presence of fluid which has leaked outside of a pump chamber and is located within a cavity of the diaphragm drive chamber. The leak alert system indicates that fluid has been detected by the fluid sensor and the shut-off control system stops operation of the pump based on fluid being detected by the fluid sensor.