One issue with the original design was that it required ice water and hot water from an external source to work.  I have designed a device that I hope will solve the logistical problems involved in replicating experiments that way by using multiple Peltier coolers to both heat and cool the water to acceptable temperatures.  I scavenged parts from two wine chillers to make the bulk of this device.  Current draw should be somewhere just below 12 amps at 12 volts, so I will need to be upgrading my power supply!

My hope is that I can achieve an adequate difference in temperatures quickly enough to be able to conduct one test per half hour.  We will see!