I would recommend running a second circuit then. Power half of the tank off of one, and half off of the other. One GFCI per circuit and you'll be safe and the tank will have redundant power supplies.
FWIW, I have 2 circuits in my tank room and right now they run different tanks. There's a high likelihood that I will swap over to this exact setup.
I do have a ground probe in each tank. Whether or not the tank crashes, I can't enjoy or maintain it if I am dead. Electricity and saltwater are not a joke. It only takes milliamps to be fatal
Exactly. As my wife reminds me all the time "it's about amps not volts!"
I have two circuits running my system. Apex base on one with a power bar, and the other power bar on the other. If the non Apex base goes down, I'm ok. If the base goes down, I get an email. My tank can survive for hours without running.
I also have a battery pack air stone just in case. This will keep it oxygenated and buy more time.
Heat isn't much of an issue since it decreases slowly and the live stock will be fine for a long time.
I also installed a whole house natural gas backup generator for when the main power goes out, just for the tank!