The Seapora Storm DC Skimmer is a powerful and affordable in-sump skimmer that removes dissolved organic waste from your aquarium to promote a cleaner and healthier environment for its inhabitants. High-Performance Controllable Motion Pump: easy adjustment of flow rate. "Feed" mode for feeding, to decrease the chance of over-flowing. Features collection cup for easy maintenance, with adjustable air silencer and highly efficient bubble chambers that feature custom diffusers.