Frosch

Hi, I am new to this forum so it may have been answered before. We are thinking of getting/raising a couple of Frogs in Spring when there is tadpoles. One thing that I am still somewhat unclear on is what kind of cleaning/upkeep will be required once the vivarium is occupied. Does it need to be completely emptied and cleaned on a regular basis? Or is it just a case of changing the water in the frog pool? Also I was thinking of putting a little waterfall in there - is that a done thing? Thank you for any help.