Static Shock?!?

[Yedgy]

Once in a while, I get what feels like a static shock when I first touch the water. It's not continuous, and it's apparently not enough of a shock to trip the GFCI (I've tested it to be sure it's working). Once I get the shock, I can put my hand in the water with no further shock. Is this normal? Would a grounding probe help? It isn't painful, but all those electrical wires plus highly conductive water = worry.

Thanks!