Zoo Med's Natural Forest Tile Panel Backgrounds for Terrariums make the perfect natural background for your terrarium or vivarium. Panels are precut and may be used in either a Zoo Med Naturalistic Terrarium or custom cut for another kind of terrarium. Natural forest tile panels for terrarium/vivarium backgrounds. These panels are precut to fit zoo meds naturalistic terrarium or can be cut for custom sizes. They are perfect for high-humidity environments as they are highly resistant to mold or mildew. Size: 12 x 18.: Size: 12 X 18 in.