Awi, do you have a ground in your tank? In my thinking, i could be wrong here im not an electrician, if you had a ground then it would pick up the voltage. If that ground was connected to a GFCI then it should trip it. If the GFCI were tripped then you would go looking for the problem as soon as you noticed some of your stuff had no power. If there is an electrician reading along please pipe in.