Because corn snakes are most active around nighttime, many say that lighting beyond the natural cycle of the lights in your house/reptile room is not required. This is incorrect. Just as there is bright daylight in the wild, corn snakes need a distinct day/night cycle in captivity as well. Providing terrarium-specific lighting is very beneficial for regulating your snake’s natural biorhythms and encouraging natural behaviors.
Simply speaking, your corn snake’s lights should be on 12 hours/day. If you want to create a more natural day/night cycle for your pet, try a graduated cycle of 13 hours of light during summer and 11 hours during winter. Providing a seasonal light cycle can help promote more natural hormonal rhythms in your snake, resulting in better overall health.
Wild corn snakes are sometimes exposed to varying levels of UVB wavelengths during the day. Conventional wisdom dictates that UVB is not required for most snakes, and it’s true that they can live without it, as has been proven by years of captive breeding. BUT — recent studies (especially work by Frances Baines) increasingly suggest that UVB can be very beneficial for a snake’s mental and physical health. This goes beyond the requirements of survival and is part of ensuring that the animal thrives in captivity. In fact, Does exposure to UVB light influence the growth rates and behaviour of hatchling Corn Snakes, Pantherophis guttatus? outright recommends using UVB lighting for captive corn snakes, and it can be easily argued that UVB provision is also required to comply with Mellor’s 5 provisions of animal welfare in captivity.
ReptiFiles strongly recommends providing UVB to all pet reptiles, including corn snakes. To include UVB in your husbandry, use a T5 HO UVB fluorescent tube like the 22″ Zoo Med Reptisun T5 HO 5.0 or 22″ Arcadia Forest 6% and replace every 12 months. Avoid all other brands/types of UVB bulbs. I specifically recommend Zoo Med and Arcadia because other brands have proven to be unreliable and even unsafe.
Your corn snake should receive maximum UVI of 2.0-3.0 in the basking area, which should be the area of highest temperature and UV in the enclosure. The strength of UVB that a reptile is exposed to depends on its distance from the bulb, so it’s very important to take distance into consideration when you’re installing the basking area. Specifically, you need to pay attention to the distance between the UVB bulb and the snake’s back when it’s on the basking surface:
Lamp mounted above mesh (recommended for safety):
Without mesh obstruction:
You will need to mount your UVB bulb in a Vivarium Electronics T5 HO or Arcadia ProT5 fixture. Optimal use distance is likely to be more variable if you use something different.
The above distance recommendations assume a ~35% mesh block. It is strongly recommended to use a Solarmeter 6.5 to determine the best placement. For more details on adjusting basking distance based on mesh obstruction, see the Facebook group Reptile Lighting > Guides > Guide 1: Using T5-HO lamps above a Mesh Screen.
If you need more distance between your snake and the UVB in the basking area than your enclosure’s setup will allow, I recommend using a UVB Riser to strategically increase the distance for your snake’s safety. (Here’s a product review I did for one by Custom Reptile Habitats in 2022!)
Your UVB will need to be changed every 12 months to remain effective, even if it still seems to be working.
Nighttime lighting such as a colored bulb is not necessary. At best, it is likely to disrupt your snake’s circadian rhythm (day/night cycle). At worst, it may damage your snake’s eyesight and/or mental health. In other words: Don’t waste your money.