I read that Greek tortoises need to have a warmer temperature than other species. Would you recommend using a ceramic heat emmitter 24/7 or would you recommend just using it at night?
you should use it for the basking spot all day with no other heat bulb, if you are going to use it all day get a flurescent uvb bulb that puts of little heat,if you have a uvb that puts off heat only use it at night they need a warmer side and cooler side so put it on one of the sides
Torties, as Danny has said depending on where you live and the temps the torts are in during the summer you probably do not need additional heat at night during the summer. winter may be different. Then you may need to provide additional heat at night with a ceramic heat emitter or infrared heat bulb. Please do not leave a light (white) on during the night. The torts do need their sleep and light they can see will disturb there sleep patterns. http://www.pettortoise.co.uk/tortoise_climate.php
And as Danny said depending on your type of Greek A temperature gradient of 75° - 85° F daytime should be provided with a basking area of 95° F. Nighttime temperatures can be allowed to drop to 65-75° F.