Abstract: The apparatus includes a fermentation tank of a type including a cylindrical tank shell and a downwardly-directed frustoconical tank bottom affixed to a bottom edge of the cylindrical tank shell. An upwardly-directed frustoconical support positioned below the cylindrical tank is configured to have a centrally located aperture for receiving and supporting a lower portion of the tank bottom. The tank includes an outer cylindrical sleeve configured to receive the cylindrical tank shell, tank bottom, and support to form a tank assembly, wherein the assembly includes an annular gap between the tank shell and sleeve, and a cavity between the sleeve, tank bottom, and support. Rigid foam insulation is then filled within the annular gap and cavity to provide structural rigidity to the assembly as well as insulative properties to maintain the stored liquid at a desired temperature.