all my Carpets can take that level of night time temps mate...
that said i had one Jag that i had to heat 24/7 or she kept getting a R.I.
in winter (their cooling cycle) my Diamonds get 2 to 3 hours basking light and 2 to 3 hours 2.0 natural daylight UVB per day,then no more heat,like i said i set a heat mat at 50F,so they don't go any lower...
that said,imo a Diamond would be able to take the odd night at much lower temps,i'm just not willing to experiment with my pride and joy 2.2 Diamond group
i agree that other species may die quick at Carpet night time low temperatures
cheers shaun