Originally Posted by Daleo
Because there is supposed to be a thermostat to control the air temperature. And a day lamp would be on off on off all day keeping the temperature constant.
I think what Daleo means is that with a heat source you need to have a thermostat that controls it. The thermostat is set to a specific temperature and will turn the heat source off when the thermostat senses it is above that temperature, then back on when it dips below that temperature. So if you are using a heat source with visible light as your hedgie's only light source, it will not get the amount of daylight it needs to keep on schedule.