heat gradient

Hi I'm just wondering how I can get the right heat gradient in a vivexotic 2ft as I would like the basking to be 38-40 and the cool end around 24-25 but every bulb in there just seems to be an over kill any ideas?

I have been googlin' about looking for an equation to calculate temperate rise from a heatmat/bulb over a given area ie viv space and the ambient temperature ie room temp, for example if room temp is 10c then what energy is needed to increase a viv 4x2x2 to ambient 25c. thanks

Is it possible to get a decent heat gradient with a 2ft wooden viv with a ceramic or red heat bulb? Or do you only have one option with a 2ft viv: heat mat. I had planned to get a set of three 2ft vivs for my Hognoses (in about 12-18 months time), but actually two of my Royals are in 18L RUBs...

Firstly i keep my cresty in a 30x30x45 as hes only 8 grams. Ive just purchased a 45x45x60 to move him into. when would people advise i move him. is there a specific size or weight. Also ive purchased a heat mat and a heat lamp. what temps would you advise for the lamp and the heat mat. ive got...