deep litter of kiln dried sand and beech woodchips for all sections but perches and boxes scraped daily ...grills for hens but sand and chippings underneath ,flight has grills and trays underneath ,birds are healthy and happy I do change the litter every 6 months by removing half of whats their and replacing it with new so its recycling all the time as it does get dusty ...main thing with deep litter is that its bone dry