I have kind of asked about this topic but I have a new question along the same lines. I set up my tub rack with one 6 foot strip of flex watt snaked down the shelves. I am having trouble maintaining both my tubs hot spots at the same temp. There is about 10 degrees different between the two. I have rotated thermometers to see if they were reading wrong but ruled that out. I swapped shelves with my two tubs and no change too. I am wondering if I should cut the long strip into 3 separate pieces and wire them with their own clips.