The advantages to a false bottom are that there will be a place for excess water to drain. It also allows for a water feature in your tank.
A false bottom is not necessary though. My dart tanks dont have false bottoms. I just use a siol mixture. The thing about that is you do need to allow it to dry out a little so that excess water can evaporate (there is nowhere for excess water to drain).
In a false bottom setup you need to watch your water close so that you dont get a buildup of ammonia. In ther other you will need a water bowl that you will want to change out about twice a day to keep the ammonia from getting to high (your frogs will use the water as a bathroom).