Had a close call on Sunday when doing a water change in my prop tanks. When I put my hand straight into the water there was no issue but if I just lightly touched the surface I would get zapped with a pretty strong shock that actually hurt. I thought it was wierd and knew I must have a stray current issue but couldn't pin point it. A short time later my overflow alarm starting to beep so I went to investigate and noticed everything plugged into one of the power bars had no power so I unplugged it all and rigged up some power to get things going again. When I plugged the heater in it started to spark and there were literally flames in the sump water so I quickly unplugged it and saw the glass housing of the heater had broken in two and the element was electrifying the water. I then realized where the stray current had come from earlier - and with an obviously cracked heater glass I was very fortunate to not get electricuted so I believe the grounding probe did it's job.
Neither me, the fish or corals in the tank suffered any damage so I feel blessed - I think it could have been ugly if I didn't have the grounding probe hooked into the system. They are definately worth the few bucks I spent on them!!
Lesson learned - don't use an old glass heater as a permanent solution because
when - not if they eventually go it could get dangerous.
I will post a picture of the heater when I can but I am out of town this week and since the pix are still in my camera at home it will have to wait.
