Really, that's something that should be left to very experienced, not just knowledgeable, herpers. Very large tanks and extensive knowledge on how species interact within environments. Some people have proven successful (or so they say), but most people--even really good frog keepers, by the way--usually end up with disasters of some sort. I think that's something almost every keeper considers at some point and then decides isn't so good of an idea after a bit. The allure wears off, basically. I don't know how long you've been keeping frogs, but most of us want to keep our species singly after we have them a while 
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Got hips like Cinderella / Must be having a good shame / Talking sweet about nothing / Cookie I think you're Tame 