i am buying my tank stuff first before i get my bp. obviously i have the required equipment, but i do have a few questions regarding the setup.i bought the exo terra because i need the front opening doors. its the 18x18x36 (DxHxW). how thick do you make the substrate? i'll be using coconut husk and moss because i have some from my crested gecko. i plan on putting newspaper down first, then the probe, then husk.