it doesn't matter which lead you have in the water and which one you don't have. as well it doesn't hatter if there is stray voltages in the water as there is no path to ground so there is not way of the fish gettign a shock. they are at teh same potential as the water.
when i saw the whole stray voltages thing while googling T5HOs before i came across this and had to laugh. beign an electrician i know how electricity flows. if we are workign with live power we often will take a mat and place it under our feet, then we will take a lead from the live lines and ground it to the mat. this make it so we are the same potencial as the like lines resulting in no current (amp) transfer through our bodies.
the same thing is happening with the fish tank and stray voltages, or as they are know to us as eddi currentsin a fish tank.
Originally Posted by Jereli
As far as GFI...i am almost certain it will not trip with stray voltages. Just current. I would definitely add one either way. it can save you in worst case scenario if properly working.
a GFI won't trip unless it senses a loss in current from the live side to the neutral size, if there is a difference in amperage by .05amps it will trip, thats where its enough amperace to kill a person or atleast do serious harm to a persons heart