Yes, chameleons need 12 hours of light and 12 hours of darkness to sleep. If they don't get this then they could get stressed out and too much stress could lead them to having a heart attack and dying. I don't want to scare you but I just want you to be aware. Personally, I own a day and night timer meaning that my basking light and UVB light are set to turn on at 8am and turn off at 8pm. That makes everything much easier. When it comes to lights, I own a reptisun 5.0 UVB bulb which is popular because many people use it and for my basking I use a 60 watt normal house bulb (clear). Depending on the temperature where you're at and in your house determines the watt bulb you need to get. For me I need 60 which keeps the basking spot 78-83F which is what my little guy needs right now. Hope this helps.