I knew there was another reason other than your vast knowledge of reefing why I liked you!!! …Fellow Texas master sparky here!As a Master construction electrician for almost 50 years in Manhattan I have to slightly, very slightly disagree with you on this and will side with Dcloser12.
I also like a GFI in the panel. (in the trade they are GFIs and everywhere else they are GFCIs)
The company that invented the things, Levitan sent me to school for them when they came out another lifetime ago.
By law you are not supposed to put anything in front of the panel closer than 3' so it should always be accessible. If your panel is covered by old mops, quarantine tanks, Halloween decorations or pictures of your Mother N Law that is a fire violation and I will call the fire department on you.
The GFI near your tank will most likely be near the floor under the tank or behind the couch next to your cat. The GFI breaker in the panel can be tested or changed in about one and a half minutes but the one in the receptacle next to the cat is more difficult to change especially if you are old like me and can't get there and I don't like cats.
The receptacle can also have a number of wires connected toit and some are a horror to change.
If the thing is tripping from the ground probe, move or call an electrician because that thing won't trip anything on induced current. If you have real current leaking into the water it will always be 108-120 volts and you will light up when you stick your hand in there and touch the wet cat at the same time.
Anything less than that is normal so you can go out to dinner and try the fried calamari.
The cat will also not be happy.
Just my opinion and I am old and opinionated so you don't have to listen to me.
Have a great day.