I don't keep dart frogs so I can't help you. But you're asking for so much information that it would be hard to reply--the respondent may need to write a book to answer your broad questions. May I suggest a few resources? Joshsfrogs.com really has a lot of info--even videos on setting up an enclosure for dart frogs and videos with waterfalls. Then maybe you could have more specific questions and you may get a response on here.
Other good resources:
Reptilesmagazine.com
Blackjungleterrariumsupply.com
Also there should be an article on here under resources that should help.
Good luck!
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