Do you mean like a pauludarium or just a pond and land mass (if that makes a lick of sence) I think in a 55g, you don't have too much height, so if you do a background and the entire ground or most of it is water (that is my definition of a paukudarium) then I wouldn't do it. Now if you did a pond in the center (a large land side on the left and right with it sloping into the center) you could do a nice drip wall and keep a few neon tetras, but only a few. A large water mass in a vivarium for most frogs is not recommended from what i've heard, but if you search up hillsteam build with the search button, someone created a few thousand gallon tank with 2 massive water features, but it was a MASSIVE tank (Maybe 20 full grown people could fit in it, maybe more) and the water features maybe took up 15% of USABLE space. There was a total of around ~200 gallons of water, but a 55, like someone else posted, may seem large for a frog viv, but really isn't.