Had great success with my Container Citrus this Summer, thanks to all the Members with great advise! With Winter approaching need some information on Wintering my Citrus in my Sunroom. Will get all the morning and some afternoon sun, 8 hours. Night time temps in the Sunroom, gets down in the 50s on bitter Cold nights, upper 70s with the heater running. The Sunroom can have what i call are temperature swings. Do i need to have bottom heat on the Containers to keep the soil temp more stabil? I even have HO lightning for cloudy Days, or is artificial lightning even needed? I'll cut back on watering and fertilizer with the cooler temps. Don't want to overkill this.

I think your plants will be doing just fine without the heater and the additional lighting! I also store my plants in a lightroom during the winter months. Temperature in there may drop to 45F on deep freezing nights. This doesn't cause any problems at all.
The only thing I'm always worried about is the shock of bringing them inside. It causes the dropping of all small fruitlets and usuallly causes some leave drop also. But the plants will recover in spring!