hi
You don't need the night light. If it is cold at night a ceramic heat emitter is better. It will not put off any light and will not disturb the beardies sleep.
What type of 10.0 uvb do you have? is is a coil or a tube? is a reptiglo or a reptisun or another brand?
80-85 degrees for a basking temp is way too cool for a baby beardie it should be around 105 degrees. What are you checking the temps with? What type thermometer?
A 20 gal will be okay for a few months but by the time it is 5 months or so you will need a bigger tank.. 40 breeder is good.
and just since you are going over things:
what are you feeding? how often?
are you using calcium/vitamins? how often?
do you
bathe your beardie? if so how often?