I agree, but GFCI will only protect against electrocution. A better option might be to replace the circuit breakers for the outlets around the tank with dual AFCI/GFCI breakers. The arc fault breaker is designed to protect against fires by shutting off power to the circuit if it detects arcing, (like could occur from corroded wiring around a tank), which can create enough heat to start a fire. They run about $60, but replacing circuit breakers isn't a DIY project for many people (and probably shouldn't be for most people). According to my electrician, AFCI breakers have been required in new construction for most living area circuits for a couple of decades.
I have State Farm insurance and they sent me a
Ting device, which monitors all the circuits to detect arcing and other problems that could cause a fire. They pay for the monitoring the first 3 years, I think it is.