I personally think those temps are too cold for an ambient air temp. I aim for 80-85 and i have zero issues with my guys eating. 72-75 would be alright with me for a night drop however I keep mine consistent. I keep all my snakes in vision cages and use a radiant heat panel in conjunction with heat tape. If I used tubs/rack system I would heat the room they are in to to at least 80 and still provide belly heat on 1/3rd of the tub.just my 2 cents.