Compact, energy saving, this Koralia Pump is ideal to recreate in aquarium the natural and beneficial water motion of rivers and seas. Supplied with patented magnet-suction cup support for easy and safe positioning, Koralia can be connected to a controller and set to intervals of seconds, minutes or hours. Cable protector include (read instructions for correct positioning). Info: https://www.marinedepot.com/Hydor_Koralia_Evolution_Circulation_Pump_Powerhead_Fixed_Flow_Aquarium_Powerheads-Hydor_USA-HD00717-FIPHFF-vi.html