I have a 40watt light for heat. It’s warm where i am so she doesn’t need much. The uvb is a t5 6%. You can use mercury lamps ( there is a lot of people who say you can’t) but they put out a high amount of uvb in a small area. I have used them but i checked the uvb with a solar meter first.What UVB light is that? I upgraded to a 150 bulb.