That looks great! When using deep sand what type of sand do you use? Construction grade? Play sand? Does it matter?
Actually it's on a concrete slab that was the perfect size. We have a large cage in the house for a Galah and two blue Parrotlets; I just empty the catch tray in the aviary so that they can get the scraps and it is a surprisingly clean bedding over several weeks. Some of the seeds have sprouted so I have some grass-like patches. It might sound like nastiness due to laziness, but it isn't. Every time I go to clean it out, my wife asks me why and I can't give her a good reason ha ha.