Thats what i was saying a while ago in this thread I think about watts and the size tank and covering the screened lid. With that size tank (20 long) the CHE doesn't need to be on a thermostat unless your house gets over 72. Youll get 76-80 degrees out of it on full power with the lid covered with tin foil & a hand towel... But I keep mine on the cool side not in the middle. Keep your temps up where the hides are at this point. Its hard enough with a Glass Tanks so at least you'll know the gradient is good in both the hides this way. Thats where its most important.
You'll want a PVC enclosure in a few months I'm sure then its easy. Get on the list at AP as it took 13 weeks to get mine.