Thanks for the info. I hadn't thought of putting it along the back wall. I had seen that done on converted refrigerator and wine cooler incubators. My cooler is one of those Igloo coolers that you use to take cold sodas and beers to the beach. All the pics I've seen for this type of cooler have the heat tape on the bottom. After doing a little more online research I see people put water bottles directly on top of the heat tape or they create a small platform to lay the light diffuser on using pvc connectors and piping.