I read online that using soil in the habitat is great for maintaining humidity and promoting growth of good bacteria. I read on Czar's Frog Page that adding aquarium gravel followed by an air conditioner filter followed by the soil is a good setup.

Is this true? If so, what air conditioner filter should I use?

I'm sort of worried that the soil will cause the tank to smell bad and perhaps my room as well. I understand that using real plants in the soil will recycle the waste that the frogs produce.

Has anyone run into any issues with using soil? Should I even use this method? Maybe adding the soil by itself would be better?

And if using soil with real plants is the better route, how often should it be cleaned/changed out?

I want my frogs to have the best habitat possible. *worried first time frog owner here*...lol

Also, if I want to breed the frogs and I use some plants over the Exo Terra waterfall, would this be an ok configuration for breeding the frogs and raising the tadpoles?

I'm completely open to suggestions.