I'm not quite sure what you mean, but I assume you're talking about a hamster piling bedding up beneath the wheel? I keep the bedding that my wheel is on at just 5 inches while the rest of the cage gets about 9 inches. I usually end up moving the bedding away from the sides of the wheel as Duncan will jam the wheel and then climb on it to try and escape! So you can put less substrate or you can manually remove piled up bedding daily, or both. Best wishes
