Without the sun’s energy, all life on earth would cease to exist. It is by the sun’s energy that all life forces are driven. Although the sun and its light are very complex, there are only three elements of light that are important and easily reproducible for reptile husbandry: ultraviolet light, visible light and infrared light. In order to create these three biological aspects of sunlight artificially, Exo Terra has developed several specialized lights to be used in the natural terrarium or aqua-terrarium setting. It is important to know that it is almost impossible to accommodate all of these needs in a single light source, a combination of different light sources is necessary in most cases. The table below will help you make the right lighting choice.

Exo Terra Linear Fluorescent Bulbs

The most important feature of a Repti-Glo fluorescent bulb is its ability to emit UVB light (ultraviolet B) a component of sunlight. Not all reptiles or terrarium animals need the same amount of UVB radiation. A rainforest animal may require less UVB than a desert animal, nocturnal activity versus daylight activity also is a factor. The distance from the bulb to the animal is equally important. The further the animal is away from the bulb the lower the UVB radiation, the closer the animals are to the bulb the higher the levels of UVB.

Exo Terra’s fluorescent bulbs are classified according to their percentage of UVB output. The Repti Glo 2.0 emits very little UVB light (2%), in most cases not sufficient for vitamin D3 synthesis. For tropical and sub-tropical reptiles, 5% bulbs (Repti Glo 5.0) are perfectly adequate, provided they are correctly positioned on the terrarium, the bulb is changed regularly, and the number of hours of exposure is sufficient. 10-12 hours daily has proven to be a satisfactory exposure level for most species. Animals living in deserts, which are areas with high UVB levels, should be exposed to 10% UVB bulbs (Repti Glo 10.0).

It is equally important to know that in fluorescent bulbs the more visible light emitted from the bulb the lower the UVB radiation. The Repti Glo 2.0 is a brighter bulb than the Repti Glo 10.0 bulb.


Repti Glo 2.0
The Exo Terra Repti Glo 2.0 is a general light source with a high visual light output and a very high color rendering index (CRI), but a lower 2% UVB radiation. This bulb is suitable for snakes, amphibians, frogs, toads, salamanders and nocturnal animals. Plants will thrive under this light as well. It is also a perfect complementary light to a second higher UVB bulb to boost visual light in the terrarium.

Repti Glo 5.0
The Exo Terra Repti Glo 5.0 has a moderate to high 5% UVB output, similar to that of shady environments such as rain forests and other tropical locations. Reptiles living in these habitats receive less UV radiation because of the many climate and habitat conditions that prevents direct sunlight from reaching them or their basking areas.

Repti Glo 10.0
The Exo Terra Repti Glo 10.0 has a very high 10% UVB output similar to that associated with desert environments. Desert locations receive more direct sunlight than any other because of fewer clouds, less air humidity and no plants or trees to provide shade. Therefore desert reptiles are exposed to more UV radiation than any other type of reptile. This bulb can also be used on screened terrariums or terrariums with dense screen covers to ensure UVB penetration. Screens can filter out as much as 50% of the UVB rays.