no, they should both be on the same side UNLESS your house is extremely cold and your cold side is below the coolest temperature that a corn snake should have. Example: if your tank is reading 65 or so on the cool side, you would need to warm the cool side up to 72-78. However, if the cool side is above 72 and the warm side is 82-85, measured by a good thermometer placed directly on the substrate on the cool and warm side respectively, then you should leave the heat lamp and the UTH on the same end. All temps are listed in Fahrenheit.
sue fredrick