Hello

I doubt you will be able to maintain the humidity properly if the top of the enclosure is left completely open.
At least 3/4 of the screen lid should be covered with glass / plexi etc.

Here is a care sheet:
http://www.frogforum.net/tree-frogs/...caresheet.html

If these instructions are not follow - exactly- the frog with fail to thrive over time.

Additional tips:

http://www.frogforum.net/general-dis...uarantine.html

http://www.frogforum.net/general-dis...eder-bowl.html