Casper prefers to poop from a great height, usually from the perch which we call his balcony fixed to the front of his cage onto newspaper which is always below, or from one of his sleeping perches into the bottom of the cage which has a tray lined with newspaper below a pull-out set of bars presumably there to stop him from wandering around in his poop. But he rarely goes down to the bottom of his cage unless he has accidentally dropped a tasty nut or something. The grid also stops him from rummaging under the newspaper and tearing it up. He does that in his carry cage on the way to the vet. He occasionally poops into one of his food bowls. We are never sure if this is accidental or a criticism of chefs offering.
Cage gets cleaned and fresh newspaper every day. A flat surface is a lot easier to clean than cage bars. Poop-off bottle with brush head and the tub of wipes are great.
Casper on his balcony:
Casper being cute by
Jean-Pierre Declemy, on Flickr