Zoo MedHydro Balls Lightweight Expanded Clay Terrarium Substrate (2.5 lbs.; Compressed)

Perfect for all tropical species that require humidity, HydroBalls are a versatile substrate that can help you create and maintain a healthy environment for your tropical pets. Used as a base layer under regular substrate, HydroBalls create an underground water table to keep humidity levels high. You can also add a water pump (not included) to create a waterfall and generate water flow through the HydroBalls to create optimum filtration. Just adding water to the HydroBalls creates a natural 'aquifier' to increase humidity levels in your terrarium. Also perfect for root growth in live plants.