Marine aquarium cautions

[clermont]

Not an animal living in our tanks but watch out for electricity....Got a pretty good scare the other day when I stuck my hand in the tank and I could feel it. Not a strong shock more like an irritant and then the breaker blew in the house. Looked in my sump after and a heater was filled with water so it must have failed because I had vinegar bathed my return pump and was moving rock around in the sump and must have damaged it. Thinking I will get a volt meter to test water prior to sticking my hands in the tank going forward.
A GFI (believe that's what there called) would be very beneficial to every reef keeper as well.
Maybe its common sense that electricity and water don't mix but its something I stopped thinking about after the couple years I have been in the hobby.