I wouldn't tape anything being that your humidity is higher. Ambient temps DO NOT have to be in the 80's. My temps are around 77-80 mostly averaging at 78 and has never given me a problem. Don't go nuts trying to be dead on balls. I would strive for 50-60% humidity, 77-80 ambient, 89-92 hot spot. Thats perfect conditions. Its never going to be exact all the time, and there will be a slight variance time to time. I don't understand how your humidity is so high with that many holes lol I have way less then that and I maintain 50-60% easy. Did you wet the substrate?