Put all of your rock in rubbermaid bins with fresh made saltwater. Take out all of your live sand and try your best to rinse it. If you can't, then toss it and buy fresh/new. You don't want old nitrate and phosphate to be leaked into a brand new system. Put new livesand down, fill the tank half way with saltwater, add your old rock and a few pounds of freshly cured rock, then fill up the rest of the tank and get the pumps and everything going again. Have a 50% water change ready in a few days to head off the ammonia spike to try to save some of the microfauna. Eventually your tank will get back to it's former glory, but it will take time.
I suggest you try to find the piece of equipment that is putting so much voltage into your water. Put all of your equipment in a rubbermaid with saltwater to clean and wash everything, then test your water with the voltometer. Start unplugging each piece of equipment until you find the one that is causing the high voltage, then replace it with a new one. A titanium grounding probe will channel stray voltage out of the tank too. Also, before you set up your new tank, install a GFCI unit on all of your power outlets to your tank. If a ground fault happens, it will immediately cut power off to the tank. Someone is bound to notice that the lights aren't on and the water isn't moving. That's better than electrocuting your fish, neh?