Prior studies of indirect water storage tanks that employ an immersed heat exchanger to discharge the stored energy identified two potential methods of improving the rate of energy extraction: (1) an internal baffle to increase the velocity across the heat exchanger and (2) a divided storage compartment to achieve thermal stratification. The relative benefits of the two options are compared and recommendations for implementation are provided based in part on measurements in a 350 l tank with a 10 m long, $0.3 m2$ coiled tubular heat exchanger.