ProRep Vermiculite Coarse

ProRep Vermiculite Coarse is a natural incubation medium and invertebrate substrate trusted by reptile keepers across the UK. Made from exfoliated volcanic rock, it is completely inert — it will not decay, break down, or develop mould, making it a reliable foundation for egg incubation setups and tarantula or spider enclosures alike. Available in a range of sizes to suit single clutches through to large-scale incubation programmes.

What It Is

This is 100% natural vermiculite in a coarse grade, sourced from exfoliated volcanic rock. Its inert composition means it introduces no organic matter that could compromise your incubation environment, and it holds moisture consistently without becoming waterlogged or breaking down over time.

Using It as an Incubation Medium

To incubate reptile eggs, add a generous layer of moistened vermiculite to your incubation box before placing eggs. A common starting ratio is 2 parts vermiculite to 1 part water by weight, though exact moisture requirements vary between species — always research the specific needs of the species you are working with before eggs are laid. Place eggs with the upper third exposed, and ensure eggs are kept in their original orientation from the laying site. Where possible, eggs should not touch one another during the incubation period.

Using It as a Spider or Invertebrate Substrate

Coarse vermiculite works well as a substrate or substrate component for tarantulas and other spiders, providing a stable, mould-resistant base that holds burrow structure and manages humidity effectively without decomposing.

Key Properties

• 100% natural exfoliated volcanic rock
• Inert — will not decay or go mouldy
• Coarse grade for incubation and invertebrate use
• Consistent moisture retention without waterlogging
• Suitable as a standalone medium or mixed substrate

Choose the size that matches your setup — whether you are incubating a single clutch or running multiple incubators through a breeding season, ProRep Vermiculite Coarse is available in options to cover the scale of your operation. Always have your incubator prepared and your species research complete before eggs are laid.