20 Gal. Heating Lamp Question

[Skiploder]

I keep her in my room, wich stays between 71-73 degrees. the surface temp on the UTH is only 81 degrees.

The ambient in your room is probably too low for a UTH to overcome. UTHs, even the best ones, do next to nothing for raising the overall ambient temp - especially in a glass aquarium

In order to figure out how effective your current bulb is, you need to use a temp gun to shoot the basking spot beneath it, the area between the basking spot and the cool end and the cool end.

Those three readings will tell you how effective your current bulb is.

What are using to control the heat? For example a rheostat or a thermostat........