Your common cool down temps for brumation are anywhere between 45-60 (nothing below freezing). I currently have 2 rats in their brumation state at around 55-60. You dont have to cool them down unless you plan on breeding or unless they are wild caught and its their first time in captivity.
This is the first year for my wild rats being in captivity so they just naturally went into their brumation stage, next year they will not be going into their brumation stage.
Good luck! If you have any questions feel free to pm me
1.0 Green Anaconda-(No Name)
0.1 Dumerils Boa-(Pandora)
0.1 Leucistic Texas Rat-(Luna)
1.0 Albino Texas Rat-(Jolly)
1.0 Hypo Everglades Rat-(Koba)
0.0.2 Black Rat-(Bonne & Clyde)
1.0 Ornate Nile Monitor-(Dracula)
0.0.1 Green Bottle Blue Tarantula-(No Name)
Putting your snakes through the brumation period during winter season is something you DONT have to do unless you are wanting to breed. Otherwise they are fine at 75-85
1.0 Green Anaconda-(No Name)
0.1 Dumerils Boa-(Pandora)
0.1 Leucistic Texas Rat-(Luna)
1.0 Albino Texas Rat-(Jolly)
1.0 Hypo Everglades Rat-(Koba)
0.0.2 Black Rat-(Bonne & Clyde)
1.0 Ornate Nile Monitor-(Dracula)
0.0.1 Green Bottle Blue Tarantula-(No Name)