ok so these new exo terra vivs that I got are completely sealed with a glass top. It makes the front glass door very wet and full of condensation. I guess the only way to clear this up would be to drill holes into the glass top. What size do you think would work? How many? Drilling glass scares me as I've never done it before. Any tips? I just don't want to shatter the glass as the top is siliconed down from both sides making it a pain the remove it if I shatter them. I have 6 18" cube vivs to do.