Zoo Med Eco Earth Expandable Substrate is a coconut husk that is ideal for burrowing animals, providing a perfect environment for them to thrive in. It can be used as a more damp substrate, or left to dry slightly if needed, and also does well when mixed with sand to provide a digging environment. This comes in a pre-packed brick, which you just need to add water to let it expand. When used as moist bedding it can help to increase humidity in an enclosure, egg laying chamber, or hide, meaning it can suit almost every reptile need. For small animals, snakes and tarantulas the substrate can be used dry (it should be moistened to expand then dried in the sun). Each block will make 7-8 litres of substrate. The Zoo Med Eco Earth Loose Coconut Fiber Substrate is a product made from the husks of coconuts and can be safely composted or recycled into potted plants or gardens. Add Eco Earth loose coconut fiber substrate on top of Zoo Meds HydroBalls to create an ideal drainage layer for optimum plant growth, humidity, and drainage in naturalistic terrariums. It comes in a pack of two. Ideal Usage One compressed coconut fiber will expand to make 7-8 liters of substrate that are ideal for all types of reptiles, amphibians, small animals, or insects. Made from an eco-friendly renewable resource, it naturally absorbs and breaks down odors and waste products. Use it in a damp way for tropical species, and a dry way for desert species.