I keep my house quite cool year round, and have found that my Uro appreciates some heat in his cage at night. I have used both "night lights" and ceramic heat emitters (CHEs), and also prefer the ceramic heat emitters. Though initially more expensive, they last much longer, and emit no light. This is of particular note if you keep your lizards in a bedroom or guest room.
I have used the black lights, and the red lights for night lights, and have found that they work fine, if high enough wattage (around 75 - 100 watts for my 40 gallon breeder tank).
With that said I do still prefer the CHEs. I just leave them on 24/7 and add basking and UVB lights during the day. It seems to work quite well.
I hope that helps!
Elizabeth

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1.0 Uro Archimedes
0.0 Fish
0.1 Sulcata Minnie
1.1 Iguanas Flik and Loki
0.1 Newfoundland Jasmine
0.1 Feline Winter
Indiana & Wisconsin