Angel, I would like to respectfully disagree with you on the 3 degree swing being ok. I know I'm new to salt water, but even with freshwater if I had a tank with a 24 hour temperature swing of 3 degrees I would be pretty worried. These fish and corals are from habitats where the temperature swings VERY little on an annual basis. I think getting that temp swing as little as is possible is very important. Even if it means keeping the tank at 80 with 0 change in temp.
Disagree all you want the gloves are coming now buddy!!!!! :evil:
Naw just kidding,

I have seen many a tanks with a wide range of temp settings as mentioned here. And contrary to popular belief even the ocean has temp changes albeit in more gradual time than in our tanks. I have been having temp swings of three degrees for ever with no problems not even ich. I am working on trying to stabilize it better though and will be investing in a better chiller this year. So it is OK to respectfully disagree because that what this whole thing is about getting informationa nd making your own decisions based on that info. Anythng more than 3 degrees would worry me immensely.