thermometer probe in my tub I have heard that you place it directly on top of where the uth goes. is this right. And when i do that the temp stays at a steady 88 but when i put in my aspen and put the probe ontop of the aspen then the highest the temp gets is 71, how do i increase ambient temp in my tub. and dont worry i'm not experimenting with my bp in the tub. he is in his tank until i can find how to get the temp and humidity right. please help