Galápagos Hermit Crab Substrate is a perfect mixture of tropicoco soil and sand. Designed to mimic their natural environment, this time-tested substrate helps maintain humidity and encourages natural burrowing. Digging and burrowing is essential for a healthy Hermit Crab because it promotes molting hormones and provides them with a feeling of safety. Comes in a resealable stand-up bag to prevent spills and keep your extra substrate clean.