Best substrate for crested geckos
Crested geckos come from humid New Caledonian forest, so a moisture-holding natural substrate does most of the work of keeping humidity up. Very small geckos are the exception: they do better on paper towel. This guide compares the options ReptiFiles recommends, plus the ones it says to avoid.
Quick comparison
| Substrate | Type | Pros | Cons | Verdict |
|---|---|---|---|---|
| DIY mix: 60% organic topsoil / 40% coco fiber | Natural | The ReptiFiles recipe; cheap; holds humidity | Source topsoil with no additives; you have to mix it yourself | Best value |
| Coconut fiber (Zoo Med Eco Earth, Exo Terra Plantation Soil) | Natural | Widely sold; good moisture retention | Can dry out on the surface; loose particles | Easy pick |
| Zoo Med ReptiSoil | Natural premix | Listed by ReptiFiles; ready to use | Needs a drainage layer so it doesn't get waterlogged | Good |
| Bio Dude Terra Fauna / Josh's Frogs Tropical BioBedding | Bioactive | With a cleanup crew, waste breaks down in place | More setup: you also need drainage, plants, and the clean-up crew | Best bioactive |
| Paper towel / blue shop towel | Artificial | No impaction risk; cheap; ReptiFiles suggests it for geckos under 13 g | Doesn't hold humidity; replace weekly | Juveniles |
| Bark/wood chips, pine/cedar, reptile carpet, shelf liner | — | — | ReptiFiles flags these for impaction risk, toxic oils, snagged toes, or off-gassing | Avoid |
Zoo Med Eco Earth coconut fiber
Compressed coconut fiber that you rehydrate before use. ReptiFiles names Eco Earth as a coconut-fiber option. On its own or mixed 40/60 with plain organic topsoil, it fits the 2–4″ layer depth ReptiFiles recommends.
Zoo Med ReptiSoil
A premixed natural substrate that ReptiFiles recommends for crested geckos. Put it over a drainage layer, then cover it with leaf litter. Spot-clean daily and replace it monthly unless the setup is bioactive.
Josh's Frogs Tropical BioBedding
A tropical bioactive mix that ReptiFiles recommends. It only works as bioactive once you add springtails and isopods, plus live plants.
Zoo Med HydroBalls (drainage layer)
Clay balls that go under a mesh barrier. ReptiFiles recommends a drainage layer like this, or Bio Dude HydroGrow, so the substrate above doesn't get saturated.
Maintenance
- Natural substrates: spot-clean daily, replace monthly. ReptiFiles says bioactive setups are self-cleaning once they're established.
- Paper towel: spot-clean daily, replace weekly.
- ReptiFiles cautions that loose substrate carries an impaction risk for crested geckos under about 13 g.