The cooling down at night is not something that is really necessary. Alot of people keep the temp the same day and night. What I should say is that if the temp falls a little it night it shouldn't affect your snake. Snakes in the wild cool at night, and it just makes it easier for me to change the bulbs out at night and the temps drop some. Also the colors look cool and the snakes don't seem to care.
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1,0 snow
1,0 amel
1,0 aney stripe motley
0,1 normal
0,1 anery
0,1 motley
1,1 oketee
1,1 tx rat
4,4 ball python
1,1 dumerils boa
1,0 columbian red tail boa
1,1 green iguana
1,0 leopard gecko
1,3 dogs
freezer full of mice & rats