Josh’s Frogs Vivarium & Pond Build Foam is perfect for constructing backgrounds and filling voids in terrariums, vivarium’s, paludariums, and ponds! No need for silicone—you can apply background material such as dry coco fiber or peat moss directly to the foam within minutes of application! This UV resistant foam expands to fill gaps and cracks, small or large, and is easy to use with the included straw applicator. The black color is ideal for uses in which appearance is a factor—much more desirable than the typical off-white foam you may be used to seeing. It also holds up well in both arid and humid environments!