Someone will be here soon in sure .. in the meantime I'd do some googling of " ceramics in vivariums " or similar .
I'm sure I saw a very similar thread in here a few days ago .
All I know is I have a Viv 5' long by 2' wide and 2'high .
I've got things running perfectly with a 250W ceramic ( it's a constant struggle to keep the humidity though ) . 250W have to be fitted with a ceramic bulb fitting / housing as they get so hot !