Very interesting to have a box turtle that is both male and female. Why do you say that? Have you seen its penis and it laying eggs?

There are light bulbs that are made for temperate zone reptiles and I would suggest you buy them the next time you need to buy bulbs. You should replace light bulbs every year because the bulb's UVB output goes down pretty quickly. Check out Bob MacCargar's website for information about the UVB needs of herps.