Leopard gecko enclosure setup: how to get it right

The leopard gecko is often called the best reptile for beginners, yet many of the common problems vets see in this species trace back to a poorly set-up enclosure: too little heat, the wrong substrate, or not enough calcium and UVB. Below is a step-by-step setup with the sizes and temperatures given by veterinary sources. For more on the species itself, see our leopard gecko profile.

How big should a leopard gecko enclosure be?

Leopard geckos live on the ground and cannot climb glass, so floor space matters more than height. Sources disagree on the minimum: VCA Animal Hospitals still lists a 10-gallon tank (about 38 litres) for one gecko, PetMD recommends 20 gallons (about 76 litres) or more for an adult, and the UK's RSPCA gives 60 cm long, 30 cm deep and 40 cm high as the minimum for one adult.

At Živalce.si we recommend a floor of at least 80 × 40 cm, because a longer enclosure makes it much easier to create a real difference between the warm and cool ends, and that difference is the heart of good care. Treat the minimum as a floor, not a target: more space means more hides and more room for the gecko to choose its own temperature.

According to the RSPCA, the enclosure must be escape-proof, well ventilated and made of a solid material that is easy to clean. Keep it away from radiators and direct sunlight, since both change the temperature inside without any control.

Temperature: the warm and cool sides

Reptiles cannot regulate their body temperature internally, so the enclosure has to offer a gradient – a warm end and a cool end. The RSPCA recommends 28–30 °C (82–86 °F) on the warm side and 24–26 °C (75–79 °F) on the cool side. A 2023 review in the Croatian Veterinary Journal gives an average preferred body temperature of 28.2 °C and suggests a warm zone of 29–33 °C with a cool zone around 24 °C. The MSD Veterinary Manual lists a preferred range of 25–30 °C.

Temperatures can drop at night: the RSPCA says extra heat is only needed if the room falls below 18 °C (64 °F). Measure both ends – PetMD recommends two thermometers, one on each side. The RSPCA warns that thermostats are not always accurate, so check temperatures daily with a digital thermometer.

Which heat source should you use?

For daytime heat the RSPCA recommends a 60–100 W ceramic heater or basking lamp at one end, run on a dimming thermostat. A heat mat makes sense as extra night-time heat on an on/off thermostat: on one side wall of a wooden vivarium, or under half the base of a glass one – never under the whole floor, or the gecko has nowhere to escape the heat.

Whatever you choose must be on a thermostat. The MSD Veterinary Manual recommends that heaters are thermostat-controlled, screened from the animal and placed toward one end of the enclosure. VCA advises that the gecko should not be able to get closer than 15 cm (6 in) to a heat lamp, as it can cause burns.

Does a leopard gecko need UVB?

For a long time the answer was "no, it's nocturnal". Newer research has changed that picture. A 2020 study from Wageningen University found that young geckos given low-level UVB had higher blood vitamin D3 levels (61 vs 38 nmol/L) than geckos without it. The 2023 Croatian Veterinary Journal review also cites work showing that even short, 2-hour UVB exposure significantly raises vitamin D3 levels.

In the same Wageningen study, geckos without UVB but with dietary vitamin D3 grew just as well, so UVB is not a survival issue – but it is recommended good practice, and VCA and PetMD both describe it as recommended rather than required. The RSPCA suggests a 2–5% UVB tube, half to a third of the enclosure length, at the warm end, giving a UV index of about 0.7 in the basking zone and dropping to zero in the shade. Run the lights for 12 hours, then 12 hours of darkness.

UVB tubes lose output long before they stop glowing. PetMD advises replacing them every 6 months, the MSD Veterinary Manual every 9–12 months for fluorescent tubes – follow the manufacturer's guidance and note the replacement date.

Hides and a humid hide

Leopard geckos spend the day hidden. PetMD recommends two hides – one at the warm end and one at the cool end – plus a humid hide lined with damp sphagnum moss to help with shedding. The RSPCA adds low, sturdy branches or rocks for climbing. Place hides so the gecko has cover at every temperature: if the only hide is on the cool side, it will stay hidden and too cold rather than come out to warm up.

What humidity does a leopard gecko need?

Leopard geckos come from dry, rocky habitats and need dry air. The RSPCA gives around 30–40%, measured with a hygrometer at the cool end, while PetMD says under 50%. The MSD Veterinary Manual even lists 20–30%, but notes that humidity needs are much higher during shedding – which is why you provide a humid hide, not a damp enclosure.

Which substrate is safe?

The safest options are paper towels (especially for juveniles and quarantine) and slate or ceramic tiles. VCA advises against coarse sand, corncob bedding and crushed walnut shell; PetMD against gravel, wood chips and walnut shells. The MSD Veterinary Manual warns that ground-dwelling reptiles often swallow gravel and pebbles, which can block the gut.

The RSPCA also lists a mix of roughly 50% organic soil and 50% sand that allows digging – but for young animals, paper towels or tiles are the safer choice. If you use a loose substrate, PetMD suggests offering insects in a dish so the gecko doesn't swallow substrate while hunting.

The most common setup mistakes

• One temperature throughout – with no cool end, the gecko cannot cool down.
• A heater with no thermostat, or a heat rock – a risk of burns and overheating.
• Sand under a young gecko – it can be swallowed while hunting insects.
• No UVB and no calcium – the combination that leads to metabolic bone disease.
• Two geckos together – the RSPCA recommends keeping leopard geckos alone, as they don't need company and can be aggressive to each other.

Be careful when comparing with other lizards: the bearded dragon is active by day and needs far stronger UVB and a hot basking spot, so don't buy equipment based on another species' care sheet. You'll find an overview of all species under terrarium animals.

When to see a vet

Is a glass tank suitable for a leopard gecko?

Yes, if it is large enough, has a ventilated, escape-proof lid and heat at one end. For glass vivaria, the RSPCA places the heat mat under half of the base.

Does a leopard gecko need a light at night?

No. The RSPCA recommends 12 hours of light and 12 hours of darkness. No light is needed at night, and extra heat only if the room drops below 18 °C – a thermostat-controlled heat mat is better for that than a lamp.

Can I start a juvenile in a smaller enclosure?

You can – PetMD gives at least 10 gallons (about 38 litres) for juveniles. But young geckos grow quickly, so it's more practical to buy the adult-size enclosure straight away and furnish it with plenty of hides so the youngster doesn't feel exposed.