Abstract: Pump assemblies, controllers and methods of controlling fluid pumps based on air temperatures are disclosed. One example method of controlling a fluid pump includes determining an air temperature, determining a run time of the fluid pump based on the determined air temperature, and running the fluid pump for a duration corresponding to the determined run time. One example controller for a fluid pump includes a temperature sensor for measuring an air temperature and a processor for controlling a run time of the fluid pump. The processor is operably coupled to the temperature sensor and configured to adjust the run time of the fluid pump based on a predetermined run time and the air temperature measured by the temperature sensor. The pump assemblies, controllers and methods may be used in swimming pools and various other applications.