Just to +1 the GFI thing. A while ago when I was building my 220, I had moved my existing 90 out of the way and off the GFI while The new tank was getting setup. While messing in the sump I had the heater glass explode IN MY HAND while live. And I mean the whole glass shield came off.
Now, that did give me quite the shock, electrically and mentally as the using was sparking and zapping as I held on to it.
Since then, I always have a GFI. Thankfully the wife was standing there and the power bar it was plugged into was withing her reach
Save so grief and drip loop power cords, install a GFI and don't be silly. 120V might not kill you but it will at least hurt -- a lot.