Choosing a Substrate
Substrate isn't just a decorative floor — it holds humidity, supports burrowing behaviour, and sits right in the middle of one of the hobby's most genuinely disputed safety questions: sand.
Key facts
- Substrate does several jobs at once: humidity retention, supporting burrowing, ease of cleaning, and appearance.
- Paper, reptile carpet and tile are the safest choices against impaction risk, though also the plainest-looking.
- Sand as a substrate remains genuinely disputed in the community: some keepers report impaction cases, others report none — there is no settled verdict.
What substrate actually does
Substrate affects humidity retention and regulation, supports natural burrowing behaviour in species that show it, determines how easy the terrarium is to clean, and shapes the overall look of the setup.
Substrate types and what they suit
- Paper towel, newspaper, reptile carpet or tile — rule out impaction risk entirely, and are the easiest to clean; tile also holds heat well under a basking spot. Commonly used for quarantine and juvenile animals.
- Coconut fiber (coir) — retains moisture well and stays low-dust, but used as a thick standalone layer carries more accidental-ingestion risk than a small amount used in, say, a humid hide.
- Sand — a genuinely disputed choice in the community: some keepers report impaction cases in their animals, others have had none. Where it is used, sources recommend a fine, additive-free sand and close monitoring of the animal.
- Bioactive substrate mixes (soil, clay and similar components) — used in bioactive setups with live clean-up organisms.
Impaction risk
The mechanism is well understood: loose substrate particles get swallowed — often accidentally, taken in along with food picked up off the substrate — and build up in the digestive tract, sometimes requiring veterinary or even surgical treatment. How large that risk actually is for specific loose substrates remains a genuine point of disagreement in the community, and sources do not give a single settled verdict.
Depth for burrowing species
Burrowing species need a substrate layer deep enough to actually tunnel in — we couldn't find a reliably cited exact depth figure, so this stays a qualitative guideline rather than a number.