With a vertical tank, the best way to do this seem's to be siliconing a bottom piece of glass in, then attatching a glass door with hinges, and having a framed screen at the top to help air circulate, But is there a standard size for this screen "window" at the top depending on tank size, or does is depend on the humidity requirement of the animal in the tank?

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"Nobody can do Everything, but Everybody can do Something."

There isn't really a standard size. Give it a whirl. If your humidity is too low, plastic some more off.

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My name is Liz
Do what's best for the animal, not what's best for you.

You'll find that it doesn't take much open area for a lot of the humidity to escape.

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Mike
"Never worry about numbers. Help one person at a time, and always start with the person nearest you." - Mother Teresa

plus, natural humidity changes with the seasons. I the summer, I don't need any plastic over my tank, but in the winter, its almost all the way buttoned up.

__________________
My name is Liz
Do what's best for the animal, not what's best for you.

So then would a slightly bigger screen then be best, (maybe one fourth exposed) for airflow, then devise a simple way to add more panels to expand over the screen as needed?

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"Nobody can do Everything, but Everybody can do Something."

Thats what I do with my air vents. I add plexi as needed.

__________________
My name is Liz
Do what's best for the animal, not what's best for you.