Question: do uvb bulbs go bad?
Answer: Compact Fluorescent UVB bulbs should be replaced every 6 months. As a general rule, reptiles or amphibians should be able to bask within 12″ of the bulb. ... UVB 100 bulbs are approximately equivalent to the former 5.0 bulbs, while UVB 150 bulbs roughly equate to the previous 10.0 bulbs.