The Reef Octopus controllable Direct Current “DC” water pumps are the latest in variable speed flow technology and allows for refined control, enhanced performance and efficiency. The vast majority of circulation pumps available to hobbyist are alternating current "AC" pumps (the type of power that comes out of your wall outlet). Direct current pumps have several key advantages over traditional AC pumps. Most notably,you can control the rotational speed of the motor, thus electronically control water flow rates. DC pumps are also more efficient than AC pumps and produce less heat per volume of flow.
*Now the aquarist can have full control of the water flow through their sump, reactors, filters or closed loop systems!!!