Today I decided to switch off of loose substrate. I was using a reptile bark, I had used aspen and HATED it. Would get wet like crazy and never dry. Spot cleaning really sucked. While I was taking out the reptile bark you wouldnt believe what you miss when spot cleaning. The urine seeps to the bottom, leaving stains. Also taking every piece of substrate out that had fecal matter on it is almost impossible. Plus you wont always see the urine, unlike urates which are easy to spot always. I now have 140 feet of 28 inch wide brown contractors paper. And that cost 9.46. Now thats a deal. Cant really beat it, and you can cut it to the size you want. Its perfect for my 4x2's. Honestly, I dont believe you can get a true clean with loose substrate. With this contractors paper or paper towels, newspaper, as soon as it is soiled, you take it out clean the ENTIRE cage and the bacteria count is exponetialy less.