Abstract: The present invention advances tank-based aquaculture by providing a low cost, high efficiency solid waste separator. The invention combines the simplicity of centrifugal-gravitational separation with the practicality of automatic separator cleaning. Low-pressure air from a blower or air pump induces water flow through the separator. The compressed air source is also used to purge accumulated sludge from the separator and to scour internal separator surfaces. Installation of a captive floating granular media bed within the separator further stabilizes the centrifugal flow pattern, enhances the scouring action during sludge flushing events, and provides substrate for nitrifying bacteria colonization. Separator purging and scouring processes are simply and easily automated with small, low-voltage electric valves and timers. Operational cost-savings are magnified in multiple tank systems where multiple separators are operated by a centralized compressed air system and controller.