Well for one, seperate cages is like seperate bedrooms, if you catch my drift. 
Green tree frogs? I'm more experiance on Cubans but it's possible that the males may also get black swollen pads on their thumbs during breeding season. Look out for those.
Also, females are -usually- bigger, so that the male is able to hop ontop and initiate aplexus.
All I can say for positive info is either wait for more replies, or do lots of research on the net and your library. I did all of this during the past year of owning CTFs, and now I'm raising eggs! (Not their's though.
)
Good luck!
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~Shopunke