I am soon going to get an animal plastics T3 (36 x24 x12) but I am unsure of how to heatit. My room stays around 73-75 ambient, so too low for just belly heat. I have a low wattage CHE that I could use, but I am worried it will dry up the tank. I don't have the money or proper t-stat for a rhp (they need proportional right)

What should I do?
Also, for belly heat, would you recommend the heat that animal plastics sells(flex watt) pr should I get a different heat pad?