Today is day 5 for me - 6 Tolbunt Polish & 1 bonus Isbar. I came home & the power had been out for about 1.5-2 hrs. I decided to quickly candle them all to see how they were doing. I have veins in all of them!! I don't know how low the temp got, but my house stays pretty stable at 68 right now, even with the heat off (thanks goo insulation)...so I'm hoping the "intermittent cooling" didn't do any harm. Per the Brinsea instructions, you are supposed to turn on the cooling feature at day 7 for 120 minutes per day for chickens, so just a couple of days early!