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Do not use loose substrates that can be accidentally (or sometimes intentionally) consumed. They can block up your leopard gecko’s bowels and kill them; this sort of impaction, especially from substrates like sand or grit, are the leading cause of early death in captive leos. You also do not want to use a substrate that retains moisture overly well. While these are great substrates for reptiles that require humidity like the African fat-tail or golden gecko, they are not healthy for leopards, who come from dry environments and are at risk for developing respiratory infections if living within conditions that are too humid.

The best substrate to use for your leo is reptile carpet, paper towel, or slate/kitchen tile. All three cannot be ingested, are not great at retaining moisture, and are easier to clean than moss or soil. The only place where a moisture-retaining substrate is acceptable is in the leo’s moist hide, where you want it to be humid in a small area to help them shed their skin every once in a while.

The main thing to ask your self is could they get impacted. Is so you can feed the leo’s on paper towels to avoid this. As far as i know as long as you are doing that your leo’s should be fine.

whenever i have had a leopard gecko i have used maize