All the bucket does is keep the one pan full. The humidity is the same with or without it. I dont use mine as I like to open mine to fill ,that way fresh air replace the old air.
Humidity control by the vents, or area of water surface
I just stuck a large sponge, on its side, in the pan hoping it will increase surface area. Gonna see what kind of humidity that gives me. The sponge is about the size of a VHS tape, or a little thicker.
I have a Dickey, I was fooling around with the vents and when top vent open and bottom closed humit. went down a little. When i closed top and opened bottom my humit. went up to 80 % water formed on glass and in bottom tray. It look like a rain forest with all the water that formed in there.