As a medium for our crickets to lay thier eggs in we used Zoo Med Eco Earth Coconut Fiber Substrate. It is a 100% Eco Friendly Product that is made from the husks of coconuts, is sterile and holds mosture well. It can also be used in a terrarium that houses reptiles or amphibians and can be used wet or dry. Supplies are limited to what we had left from the cricket operation. Each package contains 3 compressed bricks for only $3.95

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