yes, you need to get hydrometer and thermometer, digital are the best, for thermometers i prefer infrared. at any rate you need to know these numbers and monitor them closely, most pacs would eat only after lights are off and temp cool off a few degrees, that is when they eat in a wild.
since you use UVB - what kind of pac do you have? they don't need UVB and some UVB are too bright for a regular colored pacman, while it is a big no-no for albino.

what are you using for heating?

everything else looks great! good job on that! what size is a frog in inches? we can give approximate estimate on his age. and of course pics would be helpful too