Kite, I am not arguing the fact that my cage IS hotter at the top then the bottom. My RHP is mounted to the top of the cage , so obviously the closer you get to the heat source the hotter it gets. That is a fact that you have stated and that IS a true statement. Here is how I am calling my cage a satisfactory success IMO. First off I am using 3/4" plywood that is lined with a fiberglass impregnated panel which gives me excellent insulating factors to retain built up heat. ( This is probably the biggest factor in my equation ) I do not have extra air holes drilled in the cages. I am simply using the spaces that are between the sliding glass doors and I have a spacer that keeps the glass doors open an 1/8" at each end, so there is not an overwhelming amount of air movement going on inside to mix all the air together. The panels are mounted to the far left of each cage so that they only are heating the objects under one side of the cage. The other side of the cage is naturally going to be room temp because it is un heated directly. That is the heat gradient that I refer to when I say one side is showing 86 deg. the other is 78 deg. I think one of the things that you do not approve of is that I dangle my thermostat probe rather than fix it directly to the face of the panel ( if you attach the probe directly to the face of the panel and set it for 90 deg, then it is never going to provide enough energy to do anything, so instead I have my probe positioned 3" from the floor at about the height of the snakes back because that is the spot that I want to be at 86 deg.) the face of the panel does get hot ( 172 deg to be exact ) but because it is attached to the ceiling the snake can never lay directly on them. the most that can happen is it comes into brief contact with the panel. and although 172 deg sounds hot a person can hold their hand directly on the face of the panel at that temp for at least 10 seconds before they have to pull away. Regular heat bulbs reach temps of over 600 deg at the surface face. So there you have it . Yes the top of the hide is hotter than the floor of the cage but in nature that would be true of the sun as well. Overhead heat recreates nature better than under tank heat. I have never seen a termite mound that was heated by a UTH. In the wild the sun heats the outside of the mound from over head causing the inside of the mound to heat up and create a warm environment for the snake to live. You may call what I am doing wrong and point out all kinds of scientific flaws on why my temp gradients are not laboratory perfect but the fact remains that my animals are thriving in this environment. They are on regular feed, they thermo regulate themselves from one side of the cage to the other, their sheds are good and they get regular checkups from the vet with blood workup to ensure that they are healthy. So where is the problem??