A method and apparatus for regulating the temperature of the cavitation medium for a cavitation chamber is provided. The cavitation medium is pumped through the cavitation chamber through a pair of chamber inlets and an external conduit connecting the two inlets. An external heat exchanger is used to regulate the cavitation medium temperature, the heat exchanger being either directly or indirectly coupled to the conduit. The cavitation medium can be circulated through the heat exchanger during chamber operation or, once the desired cavitation medium temperature is achieved, operation of the circulation system can be suspended. The heat exchanger can be used to lower the temperature of the cavitation medium to a temperature less than the ambient temperature; to withdraw excess heat from the cavitation medium; or to heat the cavitation medium to the desired operating temperature. The heat exchanger can utilize heated heat exchange fluid, cooled heat exchange fluid, thermoelectric coolers, heat sinks, refrigeration systems or heaters. The cavitation medium circulation system can be configured to include a filter and/or a degassing chamber.