Substrates For Use With Reptiles

Picture of Diego, a rhino iguana with aspen bedding for her substrate

What do I mean by substrate? Simple. The substrate is the bedding at the bottom of the cage that the reptile resides on.

Different Reptiles will have different needs as far as bedding is concerned. With all reptiles ingestion is a big concern, so the bedding has to be digestible if it is particulate (made up of tiny pieces). Arboreal lizards such as Iguanas (like Diego over there on the left) spend so little time on the ground that it hardly matters what is on the ground as long as it is digestible or large enough so as not to be ingested. With small lizards there is always the fear of impaction (sand can be a big problem here). Anyway, the list below outlines some of the advantages and disadvantages of some of the most common substrates

There are many substrates out there to choose from. Use common sense and keep an eye on the inhabitents of the cage and you will be all set. I know not all of them are here and I will try and add them as I learn about new ones. Remember that any "particulate" substrate can be ingested. Look at the size of the pieces and look at your animal. Will the pieces possibly fit through their digestive tract??? Use common sense everyone!

Substrates in Detail

Picture of Crested Gecko kept on paper toweling

Newspaper: Unsightly but easy to clean up and healthy by most standards. Some claim that the ink can be bad for the lizard or snake even though most black ink on newsprint is soy-based. I have never had any problems. If you believe the ink to be a problem most newspapers out there recycle a lot of unprinted newsprint. Call around you area and I'm sure you can find some. I work at a weekly paper and we always have some on hand for a small fee.
Paper Towels: Also unsightly but easy to clean. Just throw out the soiled pieces and start all over. Also easier for lizards to get a grip on to walk. Newsprint can be slick.
Cypress Mulch: By far my favorite substrate. It is non-toxic,the pieces are large enough to not get ingested. It holds moisture well and cypress is naturally bug resistant. I use this for a lot of my snakes and all my tortoises. This stuff can be hard to find in some locales. I get mine in huge bags at Agway here in New England. They sell small bags of it at the pet store but it is a major rip-off. I get a bag of at least 3 cubic feet or something for $4. They sell a tiny bag of it at the pet store for the same price.
Aspen Bedding: Supposedly this stuff is digestible if eaten in small amounts. It has a nice texture and isn't dusty. You can scoop out waste as it kind of clumps around it. My Blue Tongue Skink enjoys this stuff as he can burrow in it and make tunnels.
Sand: I know I'm going to take some flack for recommending sand for lizards. I believe that some lizards are fine when kept on sand. I keep all of my adult Leopard Geckos on sand and have never had a problem. Adult is the key word here. don't keep babies on it. Keep them on the paper towels. Now, not all lizards are fine on sand. Any lizard that eats very voraciously and gulps up big mouthfuls of sand when eating should not be kept on sand. Keep an eye on the lizard before you put him on sand. Make sure he isn't a huge lunger for his food. Then keep an eye on him after putting him on sand to make sure he isn't ingesting a lot. Any lizard that you hand feed anyway can be kept safely on sand.
Pine Bark Chips: Not a bad bedding. I don't really like it or dislike it. I used to buy it at the local garden shop. Find a distributer that can tell you for sure that it isn't treated with any chemicals or pesticides first though! This is a good bedding for snakes but makes scooping waste a problem. You can't see it as it is the same color as the chips! I do use this when I can't find the cypress. I wouldn't use it for smaller lizards like Leopard Geckos as it looks like it is hard to walk on. The pieces are too big.
Astroturf Green Carpet Stuff: I've used it before but usually the ends start to unravel which can be a problem because the tiny fibers can get wrapped around toes and cut off the circulation resulting in dropped toes. It also poses a problem with lizards trying to eat it sometimes. Convenient in that you can buy two pieces and while you wash one the other one is in there. Keep an eye on the fraying and keep your lizard well fed so he doesn't try to dine on it.
Bedding Brick: I don't know the exact name for this stuff but I recently bought some to keep the tortoise on. It may be by Zoo-Med or Tetra Terrafauna, not sure. It comes in a brown brick sized package. It is compressed somehow and when you add water to it it takes up a lot of room. One brick did it for my 36x18" breeder tank. It is some sort of small wood/dirt fiber; not exactly sure. They claim that it is totally digestible which is a good thing because the tortoise drags his food all over it and probably eats a bit of it. The particles are quite small and soft so I believe that it is digestible. This stuff gets DUSTY when dried out. I stopped using it for this reason. If you have a humidity loving species and keep it damp it is fine though.
Pine Shavings: Recently it has come to light that pine shavings can be toxic. They give off fumes that can be harmful. Not as bad as cedar but I won't use it. DO NOT EVER USE CEDAR BEDDING!!! Cedar bedding is very toxic to reptiles and will kill them! Actually it is toxic to the small mammals it is generally used for too.
Corncob Litter: No! Don't use it! It is undigestible and too large to pass thru the intestines safely. Not to mention it swells when it hits water. Can cause impaction very quickly.
Crushed Walnut Shells: This stuff goes by several brand names. Read the ingredients. I think one of them is "Lizard Litter". This stuff is the worst. Right up there with corn cob litter as far as dangerous. Crushed walnut shells are NOT digestible as it states on the package. Worse than that the pieces are shaped so they lock together if ingested and can clump up in the animals system. Avoid this at all costs.