So, I'm trying to achieve a hot spot of 88 degrees in one of my new t8's using heat tape. I have my thermostat set to 90 but the hotspot won't go over 79 and often during the night it drops to 76 or 77 which is the ambient room temp. I have measured it with a digital thermometer and a temp gun. I don't have this problem with the cage directly below it and the settings are the same. If I take the gun and measure the temp through the ceiling of the bottom cage it reads as 87-88 which is what i want. This might be a stupid question but is it possible to install the heat tape upside down?