One of the best things about crested geckos is that they thrive at room temperature. No special lights or heaters are required, but if you are in a chilly area or would like to grow real plants in your enclosures, you need to pay attention to lights, fixtures, bulbs and the heat they generate.
Please note that we do not recommend placing crested geckos near sunny windows, as this can generate heat very quickly and without warning. While the plants may benefit from the light, your gecko does not receive the beneficial UVB wavelengths through the pane of glass in the window.
Crested Gecko Temperature
It is important to keep your crested gecko between 60 & 80 degrees Fahrenheit (16-27 C), without dramatic swings. These are the safe minimum and maximum ranges. Going lower into the 50s at night is safe as long as they are not kept at this temperature for long.
Between 70 and 80 degrees is the preferred range for night and day temperatures.
Heat is important to all reptiles, as they are ectothermic or “cold blooded”. Their blood isn’t really cold, but it does mean that they require external heat to aid digestion. More specifically, reptiles and amphibians are poikiliothermic – which means that their internal temperatures are highly variable, in this case it’s due to their environment. This allows them to metabolize their food for energy in a very economical way. Geckos and other nocturnal reptiles usually are ambush predators as well as opportunistic feeders on fruit, pollen and nectar. Without the need to chase down prey or travel vast distances for seasonal vegetation, crested geckos are generally sedentary with brief periods of activity at night to look for food, explore, and reproduce.
Warmth also means they can spend their energy in growing. Their energy from food doesn’t have to be spent maintaining their body temperature as in mammals, so often you will find that they grow faster at warm temperatures with the same amount of food as with cold temperatures. Many crested geckos slow down their growth, and their appetites, during winter. A heat lamp or other heating device may be used to keep them warm, but if your room temperature is within the safe limits, it is not necessary.
Crested geckos are very heat sensitive. As stated above, they should be kept between 60 and 80 degrees, without wild swings between the extremes. A constant 75 degrees is safe, but may not be the best for a creature that relies on its environment to heat up, cool down, and digest their food. Providing a heat gradient (a warm side and cool side with median temperature in between) is a great option if someone is experienced in reptile husbandry and has a large enough tank to accommodate a basking spot of 80 and a cool spot of 65-70. A basking spot is usually a very small area of a tank that is heated by a light bulb of varying wattage. Even a CFL can emit enough heat to raise the temperature by 5-10 degrees. Be very careful if you decide to provide external heat to your tank!
You should use two types of thermometers in your enclosures. One should be a probe style which can be placed at different levels of the tank to check the ambient temperature of the space. A temperature “gun” will read the surface temperature of the glass, soil, plants, and even the body temp of a gecko! Make sure none of the readings go over 82 degrees. 80 is best to be safe. The round dial temperature gauges are sometimes unreliable for detailed readings, so please invest in the two types of thermometers above.
Be sure to check your temps multiple times a day, and when the seasons change. What works for you in winter may be MUCH too hot when summer rolls around.
A heat gradient is suitable in an enclosure 20 gallons or larger, because in a small space it may get much too hot. A well-planted tank is ideal for providing a safe heat gradient. Plants will release water vapor in response to heat, and cool the ambient temperature and provide additional moisture. People using lights in a natural terrarium for plant growth are already providing this basking spot, should the geckos choose to utilize it or not. Even CFLs will raise the temperature somewhat. There isn’t a safe guideline on what wattage bulb to use because your ambient indoor temperature will also affect the tank. Incandescent bulbs also create more heat. Be sure to check your gauges often!
Providing a basking spot in a plastic tub or tank without plants runs a dangerous risk of overheating and drying out, a deadly situation for crested geckos. Do not provide a basking spot over 82, as it introduces a LOT more risk that needs to be constantly monitored. If you are up to the task of maintaining some large, well-planted tanks, then providing a light that creates a small basking spot is fine, and is often being done unintentionally with lights designed for plant growth.
Keep in mind, many issues can be triggered by adding this heat, such as increased metabolism requiring you to feed more often, increased bacterial colonization in warm, moist environments, etc. Every tweak you make in housing can have a reaction with something else, so just keep this in mind when you build out your tanks, and understand the different risks involved.
A heat mat may be used if placed on the outside side of the tank, not underneath. Many heat mats can catch fire if damaged by wear or water. Ceramic heat emitters can be used at night.
See below for day time lighting options. We do not recommend night lights for use in heating.
Crested Gecko Humidity
A word about humidity is important here. The general guideline is to provide a dry period mid-day at around 55% with a high of 90-100% right after spraying. The level will drop to the low end after about 12 hours with adequate ventilation. A good rule of thumb is to spray the tank heavily in the evening and let it dry out during the day, with a lighter misting in the morning only if necessary. Many recommend using hygrometers to measure the humidity levels, but in our experience, most of them are wildly inaccurate and will read too high or too low. This will often depend on the location of the gauge, but also many of the cheap analog gauges are just unreliable. So invest in a good digital hygrometer if you wish, or just keep an eye on tank conditions.
When you add any sort of heat to a tank, you are going to increase evaporation within the enclosure. So a warmer tank is likely going to dry out faster, as the water in the substrate or in a bowl will rise to the top and escape through the ventilation. Most terrarium-style tanks have mesh screen at the top for this purpose; it helps cycle the air and avoid stagnation. Some also have smaller vents located lower down to draw in fresh air. It is important to have water available to help keep the tank from extreme swings in humidity, although it is recommended the tank dry out to about 55% during the day, when the lights are on, for a good moisture cycle. Spraying nightly will bring the humidity back up to 90-100% for a few hours. You don’t want the interior to be soaking wet all the time! This can lead to respiratory and shedding issues, along with harboring molds and bacteria. Yuck!
Many keepers do not provide a water dish but we recommend it in most setups, even with a misting system, especially if you live in a dry area. Clean standing water can help keep humidity stable and not dip too low during the dry period. If you will be away from home for more than a day or two, this is also extra insurance that your cresties stay hydrated. Dehydration is a silent killer and it is often seen in captive animals.
Crested Gecko Lighting
No special lights are required with these geckos, but if you have a naturalistic setup you need to give them some light. Incandescent bulbs can get VERY hot inside a small tank. Even CFL bulbs can generate heat, so be sure to monitor temperatures when using lights. A sunny window, as mentioned above, is not recommended due to heat buildup. Glass also filters out the beneficial UVB rays present in natural sunlight, so it is an ineffective source of Vitamin D3, an important nutrient generated by sun exposure or from a supplemented diet.
You may choose to provide special UVB lights for your crested geckos, but they are not necessary. They can serve to ensure adequate Vitamin D3 conversion from exposure to the UV wavelengths and promote natural behaviors. Be sure there is adequate leaf cover and hiding spots available, as constant UVB exposure can cause eye damage. 4-6 hours a day should be sufficient.
There are specialty bulbs intended either for night-time heating or for night viewing. These are either the red (often labeled as infrared) bulbs, or blue spectrum (moonlight) bulbs to be kept on all night long. Crested geckos may be able to see these wavelengths of light, and it may interrupt their normal nocturnal behaviors. It is unknown currently what colors crested geckos can see. Reptiles and amphibians are tetrachromats: they have four cone types in their retinas and probably see the same colors humans do, possibly more! Other nocturnal geckos (Tarentola chazaliae) have been shown to identify many colors in very dim light, even compared to diurnal Phelsuma day geckos. Source. They very likely can see these nighttime viewing bulbs, but find them less disturbing than daylight bulbs.
You may use these these special bulbs for brief periods in the evenings/early morning to heat the tank or to provide you with some visibility for nighttime viewing. True infrared is invisible to both humans and other animals. Good quality infrared bulbs should only emit 5% of the energy as light; the rest is heat, or thermal radiation. These are often a good option for heating many animals at night. Most red bulbs sold are just colored glass and while visible, are less harsh and irritating, similar to the colored bulbs sometimes used in photographers’ darkrooms.
Do not use black lights (ultraviolet) because these emit UVA wavelengths (similar to UVB bulbs discussed below) and they could cause health problems if used long term, such as skin and eye damage and disruption of the immune system. Source