Cyprus mulch works just great for them. It stays moist, does not mold, its easy to bury in, it has very little dust, and is easy on their digestive system if swallowed. I was advised to use this by the vice president of a herpitology society that i work with who also works with the dnr doing surveys on frogs, lizards, turtles, snakes, and birds. He has kept reptiles and amphibians for over 25 years and curently has over 70 aquarium set ups and has tried every bedding available for animals and cyprus was the one he found to suck the least and kept his pacs in it for 15 years without a problem. also lots of reputable breeders will use cyprus for pacmans and other frog species. The breeder i know that i got my mossy's from uses cyrpus for all of his reptiles and amphibians except his dendrobates for those he uses layered substrate as will i when i set up a tank.