okay lets drag another off the track while we wait on Dave's acros to decide if they caught cold or not...My opinion is the ground probes/rods is they are pretty subjective. Do they work, probably, would they create a definate short path for stray voltage to reach ground, most likely, better than the existing nuetral path (mine is tied to an 8' copperclad ground rod), another maybe. Are they really needed.....maybe...depends on the rest of your wiring.

I like the Ground Fault Interupt (GFI) breaker path instead, just not sure if I want a subpanel by the tank or just re-wire the existing circuits, (another 'one of these days' projects that needs to be done). But those I know work as designed, and would have popped open as soon as that heater started throwing stray current.

My whole reasoning is based on preferring to eliminate any stray current by finding it's source and making it go away, rather than letting it continue and just be tossed to ground without my knowledge.