Dan:
This is what I use for all my Desert Snakes. It's easy to clean and the animals get along well in it. No problems with injestion. I buy it locally at like Petco, so I don't have to pay shipping. Nice pink DHV! I love the desert vipers, they are easy keepers and cool snakes too.
Cheers!
ESU Reptile Desert Blend Lizard Litter is a sand substitute developed for desert-dwelling reptiles. Made from ground English walnut shells, it is harmless if ingested in small quantities and will easily pass through the reptile's digestive system. It is non-toxic, less abrasive and dust free. Available in 5 lb, 10 lb, 25 lb and 50 lb sizes.
Find the Sand viper 

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"Fighting on the forums is like competing in the Special Olympics, even if you win, you're still retarded."
DH June 2005