I have used all three of those substrates in the past. I like sani-chips because it is really easy to spot clean, but it does not hold burrows well. I would also NOT feed the snake in the enclosure if you are using sani-chips. Carefresh is too dusty in my opinion. Currently, I have all my sand boas on shredded aspen.
-Chris
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Christopher E. Smith
Contact
Captive Bred Herps
Wildlife Research & Consulting Services, LLC

