Most reptiles require natural sunlight to maintain optimal health. Without sunlight, reptiles are unable to properly utilize calcium. The ultraviolet B rays in sunlight help convert vitamin D3, which aids in controlling blood calcium. These rays are unable to pass through glass so reptiles need direct sunlight. During cold weather, there are special lights available that provide UV-B light. The rays in these lights are only effective for about 4 to 6 months.
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