The Reef Octopus VarioS 2S controllable skimmer pump utilizes advanced Direct Current "DC" technology to provide refined control, enhanced performance, and efficiency. Unlike traditional alternating current "AC" pumps, this pump allows for adjustable motor speed, air and water flow rates. The included VarioS Controller features a float switch connection for added security, as well as pause/feed modes for convenient tank maintenance. Additionally, the 0-10v input allows for integration with third-party controllers, providing unprecedented controllability. This pump can also be used as a replacement for various skimmer models. Please note that additional parts may be required for some models.