The Nexus Automatic System will control the cleaning cycle fully automatically. Cleaning is done on a timer, which is factory set to clean once every 3 days, however, this is easily adjustable to fit in with your pond requirements. The Nexus Automatic System will run a cleaning cycle which lasts approximately 10 minutes. Make Nexus the automatic choice: Hassle free way to clean Nexus filtration systems Automates the cleaning process of the Nexus Easily fits onto Nexus filters (post 2006 models) Control box automatically operates valves and pumps Adjustable timer controls the frequency of the cycle Easy to set up for multiple cleaning cycles Manual cycle can be carried out at touch of a button Gravity-fed and pump-fed versions available https://evolutionaquausa.com/products/filters/nexus-automatic-system/