What is UVB & UVA
UVB has a direct effect upon the immune system in skin and also stimulates production of beta endorphins, giving sunlight its feel-good factor. This range of the light spectrum is crucial for its role in skin synthesis of vitamin D3. For this to occur, sunlight must contain UVB in a particular range. Most glass and plastics block these wavelengths. The use of the incorrect % or incorrect placement will also affect how much UVB your animal is receiving. Vitamin D3 synthesis in reptiles requires warmth as well as ultraviolet light.
UVA, is essential. Reptiles have extremely good color vision, they have a fourth cone which response to UVA. UVA light helps regulate behaviors such as feeding (appetite), diurnal movement, mating and similar activities.
Heat
Reptiles bask to heat their skin in order to capture D3, increase their metabolism, drive their natural rhythm and behavior, manage fungal and bacterial infections, manage viral infections, heal wounds, digest foods, for shedding and parasite management. For these purposes they require IR heat, A, B and C. IR-A is deep tissue penetration. IR-B is moderate penetration and IR-C is superficial penetration. Reptiles require deep tissue penetration. These heat bulbs also have a small amount of UVA. They provide a full spectrum of visible light to fill in the gaps from the uvb/uva bulb
UVB/UVA Lighting
Having the correct lighting is crucial to raising a healthy tortoise. Not all lighting is created equal and not all species require the same lighting.
For higher zone species like the slider and sulcata, you will need a T5 10-12% along with the halogen flood lamp. Avoid Colored, CHE and LED. The UVB tube will be at about 15-18” from the shell depending on the species. The heat lamp, no closer than 10” from the shell.
UVB: T5 10-12%
Reflector: Reflector hood
Heat Lamps
Turtles need visible lights as well as IR heat
The wattage depends on several factors:
Enclosure size
Dome/fixture
Room temperature
Example Heat Source: PAR30 or BR30
Night Time Heat Source
Ceramic heat emitters are great for night time heat. They provide IR-C heat that helps keep your baby warm without emitting visible light which interrupts their sleep cycle.