There is no such thing as a best substrate, it's all about what works best for you. You need to decide what kind of effort you want to but into upkeep and go from there. I use screened cages for my Rhacs with a textured paper substrate. They get humidity for shedding from the lay box and light mistings. This works for me, others might be interested in soil substrates, this is also an option. You need to envision the set up you want and go with it. There are alot of acceptable substrates, but no best substrate in my opinion.
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Bill DiFabio
Azteclizard.com
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