What type of top is on the tank? That looks like an Exo Terra to me from the pics. On my Exo Terra I covered 1/2 the top with glass and the other half I cover 1/3 to 1/2 with a moist towel. It is amazing at how well the humidity stays up when the town is on there.

Not sure what the ventilation needs for an Ornate Pacman frog is though.