commonly used in reptile enclosures include those in the list below. Some
of these substrates are inappropriate for some reptiles. Some are inappropriate
for all reptiles and are included here so that you will be forewarned
against buying them despite pet store recommendations and the implied
or explicit wording on product packaging and advertisements.
should not be collected in the wild as the soil, leaves, sand, gravel,
etc., may contain organisms that are harmful to your reptile. Even if
you don't use herbicides and pesticides in your yard, these chemicals
are transported through the air as both dry and wet deposits, and so contaminate
soil, leaves, and the woody parts of plants, even those at some distance
from the point of application.
substrates, even when made from "natural" or "biodegradable"
products such as plant fibers, should not be used for any lizard who smells
with its tongue. Particles become stuck to the tongue and are swallowed.
Over time, they may build up in the gut causing a serious, even fatal,
substrates can be problematic for both snakes and lizards as it can become
stuck to their hemipenes or everted cloacal tissues when they are defecating,
being taken up into the cloaca when the tissue or hemipenes are retracted.
This can cause injury and/or infection.
particulates may get into the eyes of lizards who have no moveable eyelids,
causing irritation, injury, serious infection, or even blinding them.
Small, sharp particulates may also scratch the protective covering of
snake's eyes, which in turn may lead to infection.
the most convenient substrate is not the best substrate for the reptile.
Many substrates are being marketed towards specific species even though
they have demonstrated track records of causing serious illness, even
death, for those species.
habitats may look natural and pleasing, but they are missing the key elements
that allow the habitat to work in the wild. There are no decomposers,
those invertebrates and microorganisms that do the work breaking down
and recycling plant and animal wastes. This means that even naturalistic
habitats must be regularly cleaned, including any plants that are contaminated
with feces. When deciding whether to go with a naturalistic set up or
a more artificial setup, keep in mind the greater amount of time, effort,
and expense it will take to keep naturalistic environments clean and in
Available at aquarium stores or aquarium sections of large pet stores.
May cause problems with reptiles who may pick up the fine grains with
their tongues when lick-smelling or whose hemipenes or cloacal tissue
are everted during defecation. To some extent, all sand carries this risk.
When bought new (available in 50 lb. bags from hardware stores and
large toy stores such as Toys R Us) this is a clean, medium-sized, rounded
grain with some variation in the size and color of the grains. A good,
all-purpose choice. A good conductor of heat. Suitable for larger desert
species. Wet foods should be offered on sand-free platters or shallow
bowls, or the reptiles fed outside the enclosure in an empty or paper
towel-lined enclosure. Please note, however, that hatchlings/neonates
of desert species should be kept on non-particulate substrate for the
first 3-6 months or so until they are big enough to not experience problems
with the sand.
These densely packed fine grains do not conduct heat as evenly as
the coarser playground sand. They can generate dust that, along with the
fine sand particles themselves, stick to eyes, tongue, and body. Should
be avoided for most desert and all other species.
Not suitable for substrate or decoration. They are known to contain lead
and so are frowned upon for use with any animal. In addition, they are
extremely rough and can easily injure delicate skin and abrade shells,
leading to bacterial and fungal infections.
Wash before using to remove dust. Good heat conductor. Generally
used as the bottom layer to promote heat conduction and provide a bottom
drainage layer when live plants and a soil top dressing is used.
These are not suitable for substrate but may be used to add interest
to naturalistic habitats. They may also be used to create, when securely
glued together, decorative rocky walls and caves. They should not be used
to create climbing walls for saxicolous lizards as they are too smooth
for climbing. They can be used to form easily accessible "stepped"
walls or outcroppings for climbing and basking. The problem with using
them as a substrate is that they require copious amounts of water and
time to thoroughly wash, disinfect, and rinse the disinfectant from them
on a regular basis.
and Paper Products
Orchid bark is available in plant nurseries. It is also being packaged
and sold in pet stores for reptiles. While it is often used as the sole
substrate, is it not a good conductor of heat, and is not comfortably
burrowable by fossorial reptiles. It is not easily cleaned when kept with
messy eaters or reptiles with wet fecal deposits and so must be frequently
replaced. It is also ingested by some lizards and can cause serious, even
fatal, impactions. Small amounts may be mixed in soil and sand substrates
for reptiles for whom soil or sand is appropriate.
Plain butcher paper may be used to line the bottom of enclosures.
It is not particularly absorbent but is free of inks that may be harmful
to reptiles. Large rolls may be purchased at restaurant supply stores.
Cypress mulch is available in many areas. Used alone for some reptiles,
it is also suitable for mixing with soil to lighten it and provide a more
attractive mix. It cannot be cleaned and so has to be removed and replaced
with fresh mulch when soiled.
Layers of newspaper have been used for years in animal keeping. It
is relatively absorbent when several layers are used, and inexpensive
to replace. However, colored inks are known to be harmful to animals,
and there may also be problems with the plain black ink. (Cedar shavings
were accepted as a safe bedding for years before it was discovered that
the volatile oils caused skin, respiratory and reproductive system damage.)
In an enclosed space, an animal who relies heavily on olfactory and tongue
chemosensation may be overwhelmed by the pungent odors of the inks, even
the new soy-based inks.
Unprinted sheets may be obtained at stores selling moving supplies, or
roll ends may be obtained from some newspapers. As with printed newspaper,
it is relatively absorbent when several sheets are used, especially when
layered with paper towels. Unlike printed newspaper, the unprinted sheets
and rolls are not impregnated with potentially harmful inks.
Easily obtained and relatively inexpensive, paper towels make an excellent
substrate for reptiles with belly injuries and those in the early stages
Aspen and pine shavings may be used for snakes and fossorial lizards.
The shavings cannot be cleaned and so have to be removed and replaced
with fresh shavings when soiled. At least once a month, all shavings should
be removed and disposed of, and the entire enclosure cleaned and disinfected
before new shavings are placed inside. Cedar shavings are toxic for all
animals and should never be used in predator or prey enclosures. Cedar
and redwood should not be used in constructing housing for any animal,
nor in any furniture or paneling in a room in which any animals are housed.
Particulate litters are inappropriate for any lizard that uses its tongue
for chemoreception. The litters become stuck to the tongue and are ingested.
Even if such litters do not contain toxic chemicals, they may get stuck
in the intestines, causing a rupture or impaction. They may also get stuck
on everted hemipenes or cloacal tissue when the lizard defecates and so
be taken up into the cloaca where they may cause injury or infection.
Many litters are marketed as "natural" or "biodegradable;"
some even claim to be "digestible" and "safe for use with
reptiles." They may be made of natural materials such as wood, corncob,
nut shells, and plant fibers, but this does not mean that they will be
safely broken down and/or passed through a reptilian digestive tract.
While some small pieces may pass safely through the reptile, experienced
reptile vets can attest to the fact that too many become lodged in the
gut, requiring surgery to extract - if the impaction is caught before
it is too late.
While not technically a litter, these alfalfa-based rabbit and small mammal
food pellets may be used as a substrate for some lizards. The problem
with these pellets is that, like the walnut shell litter, they quickly
decompose and grow bacteria and fungi when they are wetted by food, water,
feces or urates. They are unsuitable for chelonians, who may develop gait
irregularities and foot deformities from trying to keep their footing
on the highly mobile pellets. They are rather rough for burrowing snakes
and smaller lizards. They may be used with green iguanas and prehensile-tailed
skinks as they will break down in the gut if eaten and so will not cause
intestinal impactions so long as the lizard is drinking regularly and
eating moistened food. The pellets must be cleaned out as soon as they
are wetted, however, or they will decompose and create an unhealthful
environment both for the lizards and the students.
Many of the litters made for cats are toxic to other animals. They
are also very dusty and can cause respiratory and eye infections. These
litters are also very dehydrating and will cause skin and other problems
for any animal kept on them.
These litters are unsuitable for reptiles. When ingested, they can
cause intestinal impactions.
Along with the risk of impaction and injury due to accidental ingestion
or uptake, corn cob can abrade the mouth of reptiles setting up ideal
conditions for mouth rot (ulcerative stomatitis) to start. Pieces may
also become lodged in the glottis of smaller reptiles and cause death
by asphyxiation. Bacterial and fungal growths resulting from cob wetted
by food, water, urates, and feces are common with corn cob and may cause
illness or skin infections in the reptiles.
litters are just plant or other pet litters repackaged and marketed to
reptile owners. They are made of wood shavings or compressed wood fibers,
compressed recycled paper fibers, processed plant fibers, or clay. They
are no safer for reptiles than other animal litters made of the same materials.
May cause intestinal impactions if ingested. The dust may cause respiratory
and eye irritations and infections. At least one brand causes almost an
immediate respiratory inflammation in prehensile-tailed skinks (Corusia
Shell Litter ("Desert Sand")
Largely nonabsorbent, these small, sharp particles are unsuitable
due to the risk of injury and impaction if ingested. The litter provides
a wonderful home for the bacteria and fungi that grow due to contamination
of the litter by spilled food, water, urates, and feces.
Sphagnum moss is suitable for use in parts of riparian, pondside, terrestrial
and fossorial enclosures. It is moistened and kept damp to provide a microclimate
of higher humidity. There have been some reports of animal keepers developing
serious fungal infections from contact with spore-infected sphagnum moss.
Moss should be periodically thoroughly dried out. It can be baked in a
250ºF (121ºC) for one hour.
Collected from Outdoors
This is unsuitable for use unless you are taking some from where a
wild-caught reptile was found and the reptile will only be kept for a
day or two before being released at the site of capture. The soil and
accompanying organic debris contains microorganisms, parasites, and environmental
toxins that may be harmful to non-native species and to native species
who have been in captivity for a long time.
Moss / Potting Soil
This is soil or pulverized sphagnum moss that has been processed and
sterilized. Bags of plain soil may be easily purchased at supermarkets,
garden centers, building supply stores, and other stores with a large
garden section. Read the packaging carefully to avoid buying those soils
that have been mixed with fertilizers, herbicides, pesticides, vermiculite,
or perlite. The latter two items may cause gut impactions if ingested,
while the former are toxic to reptiles.
This may be wild-collected or purchased in garden supply stores. It
should be baked (as described for sphagnum moss above) or frozen for at
least one month to kill the chiggers that reside in it. As with sphagnum
moss, it is suitable for use in small portions to provide microclimates
or burrowable pockets for fossorial reptiles.
The glue used in most carpeting outgasses for several days, even weeks
after installation. To ensure the safety of your reptiles, air out pieces
that will be used in their enclosures for at least a week before installing
it. When carpeting your home or school room, all animals, but especially
birds and reptiles, should be removed to a safe location for 10-14 days
until the rooms are completely aired out and toxic gasses dissipated.
Even when using carpeting with special, environmentally friendly (less
toxic, vastly reduced outgassing) backings, the animals should be removed
for several days to let outgassing chemicals dissipate thoroughly.
/ Artificial Grass
Astroturf® was the first artificial grass floor covering. Since then,
carpet manufacturers have come out with many grades of artificial grass.
Hardware stores and builder supply stores generally carry two or more
grades. The least expensive is generally the best to use. It is more flexible,
an important factor for thorough cleaning and disinfecting. The ragged
cut edges may be folded under and basted to prevent fraying. Pieces can
be washed and disinfected repeatedly before they require replacing. This
substrate can be used for any terrestrial, arboreal, or fossorial reptile.
It is cheap enough that several pieces can be cut for each enclosure and
rotated each cleaning day. The pieces of artificial grass substrate sold
in small, prepackaged pieces in many pet stores and mail order pet suppliers
is the same as the product sold in builder supply stores.
This product, also available at builder supply stores, looks more like
indoor carpeting but is made for outdoor use as well. In its construction,
it is more like the more rigid, more expensive grades of artificial grass
and is difficult to clean and disinfect.
/ Industrial Carpeting
With their deeper piles and very rigid backings, these carpets are
difficult to clean and disinfect, and should be avoided for use as a substrate.
They may be used to cover slick tubes or branches to create climbers for
lizards (similar to cat trees made for cats).
These are fibrous, absorbent pads made in sizes to fit standard-sized
enclosures. They wick the moisture away from the surface, but since most
reptile deposits are solid feces rather than urates, this feature will
not reduce cleaning time except for those species who deposit very dry,
compact pellets. Expensive when compared to suitable household products.
Terry cloth towels may be inexpensively obtained from thrift shops. They
are easily cleaned and disinfected by machine washing in hot water, soap,
and bleach. They are especially suited for reptiles in quarantine or with
Self-stick tiles may be inexpensively obtained from building supply stores.
They may be grouted around the outside edges with aquarium silicone grout.
Linoleum tiles are easily cleaned and disinfected and provide a durable
flooring for large arboreal lizards and snakes.
from Master's Thesis Classroom Reptiles, Sonoma State University, Rohnert
Park CA. 1997
for Reptiles: Caveat emptor
and Diarrhea in Green Iguanas
of Laxatives in Reptiles