Even though crested geckos are crepuscular/nocturnal, they do benefit from having some kind of light during the day. According to the UV Tool, crested geckos (referenced in the paper as Rhacodactylus ciliatus) should receive 14 hours of light per day during the summer and 10 hours of light during winter, 6 months each. This helps regulate their circadian rhythms, seasonal cycling, and improves activity, appetite, and overall health.
Don’t bother with black/blue/red light bulbs for night viewing or supplemental heat. Crested geckos’ eyes function perfectly in the dark, and providing light at night can actually mess with their day/night rhythm. Also, nightly drops in temperature are actually healthier than providing heat at night. My opinion? Save yourself a few bucks and don’t bother.
What about UVB?
Many people will tell you that UVB is not necessary for crested geckos in captivity—that they get all the vitamin D3 they need from high quality prepared diets. While it is true that not having access to UVB won’t necessarily kill a crested gecko, there is a growing body of evidence that providing UVB substantially increases health and quality of life for reptiles previously thought not to need it.
Furthermore, UVB bulbs also produce UVA light, which is a spectrum of light that reptiles can see but humans can’t. They see it like an additional color. Imagine if you had to live without the rainbow of colors in the visible light spectrum—seeing only in black and white. Wouldn’t that be dull?
For this reason, ReptiFiles recommends UVB lighting for all reptiles, including crested geckos. Since cresties are crepuscular and typically hide behind leaves during the day, you don’t need anything particularly strong. We recommend the following bulbs and fixtures:
The fixture should be mounted over the mesh.
If you have a Solarmeter 6.5 (recommended), the UVI at the basking branch should be between 1.0-2.0. If you don’t have a Solarmeter, here’s a fair baseline for distancing with each bulb type:
- Zoo Med T8 Reptisun 5.0 — 4-6″ / 15-20cm
- Arcadia T5 SO ShadeDweller 7% — 8-10″ / 20-25cm
- PRO TIP: If you use UVB, make sure that the fixture doesn’t have a piece of glass or plastic to “protect” the bulb. UVB rays are blocked by glass and plastic, rendering that bulb you just spent so much money on completely useless. Naked UVB bulbs are effective UVB bulbs!
- Basking area (top of enclosure) — 82-85°F (28-29°C)
- Cool area (bottom of enclosure) —70-75°F (21-24°C)
- Nighttime temperature — 65-72°F (18-22°C)
Note that it is very important to provide this range of temperatures! Consistent temperatures above 85°F (29°C) can cause stress and heat stroke, and consistent temperatures at or below 72°F (22°C) can cause lethargy, poor appetite, and illness.
Many people claim that it’s perfectly fine to keep a crested gecko at room temperature without a heat source, but it’s important to remember that crested geckos are ectotherms, which means that they can’t produce their own body heat and rely on natural heat sources (ie: sunlight) in their environment to help them regulate their metabolism and digest food. In my experience, the most common cause of lethargy, poor appetite, and illness in crested geckos is lack of access to a heat source.
How to Heat Your Crested Gecko’s Enclosure
The best heat source for a crested gecko is a heat lamp. White or clear low-wattage incandescent/halogen bulbs work very nicely.
If you are using a small terrarium hood like the Zoo Med Naturalistic Terrarium Hood to house your lights, I recommend the Exo Terra Daytime Heat Lamp. The exact wattage you need will depend on enclosure size, design, room temperature, and other factors, but start with the 25w and go up or down from there depending on your needs.
If you are using a small 5.5″ dome lamp like Zoo Med’s for your heat bulb, then I recommend starting with the 25w Zoo Med Repti Basking Spot Lamp. Dome lamps are also compatible with dimmers, which can be a very handy feature for controlling the basking temperature in your gecko’s enclosure.
Keep in mind that a basking area may not be safe in enclosures that are too small to accommodate an appropriate thermal gradient (ex: Kritter Keepers)!
You can make sure you’re providing an appropriate temperature gradient with a temperature gun like the Etekcity Lasergrip 774. This will give you instant readings on temps anywhere in the terrarium, which is great for peace of mind — I can’t live without mine!
Keep tabs on your crestie’s air temperatures with a quality digital probe thermometer, like the Zoo Med Digital Thermometer and Humidity Gauge, with the temperature probe placed in the basking area. Don’t use anything cheaper, like the ribbon thermometers commonly found in pet stores. You’ll save a bit of money, but it won’t be accurate and you risk accidentally cooking your gecko.
Lighting & Heating for Hatchling Crested Geckos
Hatchling crested geckos (under 13g) are often housed in small “grow-out” enclosures to keep track of their health during this vulnerable phase of life. If you have or are planning to get a hatchling crested gecko, there are some special accommodations you will need to make in terms of UVB lighting and heating.
If you put a UVB lamp on top of a hatchling’s tiny grow-out cage, you will likely expose it to dangerously high levels of UV. To keep your hatchling safe while still providing the benefits of UVB light, use a forest-strength compact coil bulb in a 5.5″ dome fixture hung from a reptile lamp stand. Turn off the light at night.
Specific products we recommend for hatchling lighting:
- Zoo Med Reptisun 5.0 Compact Fluorescent bulb
- Zilla Silver Reflector Dome, 5.5″
- Zoo Med Reptile Lamp Stand, small
There is not enough room on top of a hatchling terrarium to accommodate a heat bulb. To make sure that your gecko still gets a supplementary heat source, stick a small heat pad to one side of the enclosure, and connect that heat pad to a proportional thermostat. Place the thermostat probe between the heat pad and the glass/plastic of the enclosure to make sure that the temperatures your gecko is exposed to don’t go higher than 85°F/29°C. Turn off the heat pad at night.
Specific products we recommend for hatchling heating:
Crested geckos thrive between 60-80% humidity. This can be maintained with daily misting and a moisture-retentive substrate. Make sure to let it dry out to around 50% or even 40% before misting again—constant moisture encourages mold and mildew growth, which can make your gecko sick.
Misting is also the best way to make sure your gecko stays hydrated, as while they will drink out of a dish occasionally, they vastly prefer to lick water droplets off plants and the enclosure walls.
- PRO TIP: To save yourself from hand cramps, get a pressure sprayer like the Exo Terra 2L Mister. I can’t live without mine!
Depending on how well your terrarium holds humidity, mist at least once in the evening, and then again in the morning if needed. Your gecko will drink the droplets off the terrarium walls and decorations.
Do not use distilled, softened, or even filtered water for misting. Tap water contains minerals that are vital to your gecko’s health. Yes, this means you’ll have to clean up water spots, but it’s worth it. Here’s why.
- PRO TIP: Hard water deposits come off easily when you scrub with a lemon juice-soaked cotton ball. Severe buildup can be scraped off with a razor blade.
Keep track of the humidity levels with a quality hygrometer. Again, I recommend the Zoo Med Combometer mentioned above, since it’s a 2-in-1 package with reliable readings.