Sorry to hear about your loss.
This is my worry too, Every time I take a vacation I worry about my tank. I am on all city Power/Gas But that doesn't mean they don't have outages!
Something you might consider though is getting a bigger heater. Even if your house was 36 degrees, if your heater was big enough it should have been able to maintain your tank temp.
Just a thought...
90 Gallon Drilled Glass Tank w/ Corner Overflow: 492w (2x 150w 14,000K MH, 2x 96w Actinic CF) Coralife Aqualight Pro | Custom 34x15x15 Sump/Refugium | SWC Skimmer | Coralife Turbo-Twist 6x UV Sterilizer | Maxi-Jet Power Head w/Sure Flow Upgrade Kit | 120lbs of Live Rock | 100lbs of Live Sand