typhoonryan

I just adopted a leopard gecko from friend. He didn't have a basking lamp. After doing some reading I went ahead and got him one that is a combo uv and heat. Question: I was told it should be on 12 hours a day. Since he is nocturnal should the lamp be on at night while he is active? Also, is it true that heating rocks are not a good idea? After hearing that I took his out. He has only a den with moss and his water now. I'm totally new to lizards so any advice would be so welcomed!