Any tank deaths due to stray voltage?

[EricR]

I was thinking if you can "ground" a wire by attaching it to a metal box, isnt a rock essentially the same thing?

No. Grounded in this case means connected to the ground wire in your home AC electrical circuit ... which technically should be grounded to Earth.

Your tank essentially insulates everything in it from "ground",,, unless you have a ground probe in the tank.
*assuming no faulty/shorted equipment in the water

 

[Cory]

No. Grounded in this case means connected to the ground wire in your home AC electrical circuit ... which technically should be grounded to Earth.

Your tank essentially insulates everything in it from "ground",,, unless you have a ground probe in the tank.
*assuming no faulty/shorted equipment in the water

Makes sense. Someone told me once you can ground something by connecting it to a larger metal mass. Hence the confusion.

 

[dschuffert]

I have been fortunate; I have had tanks for 20+ years, both fresh and marine, and have not been shocked or noticed stray currents in my tanks.

 

[Lonster00]

90 Gallon Reef Tank with fish/liverock.

So Ive read through the comments regarding stray voltage. I still don't know what to think. Backstory: A week ago, I discovered that a powerhead power supply cord had detatched from the head and was just hanging in the tank. I don't know how long it had been that way, but I do know that I had gotten zapped while messing in the sump a few times for maybe two weeks. I had a powerhead and a small UV sterilizer that was about a year old. I removed them and thought I had discovered the problem. A week later was when I discovered the broken power cord. Like an idiot, I pulled the cord out of the tank before unplugging it, and it was hissing until I reached behind the tank and unplugged it. That's where I could have gotten electrocuted but I overreacted. About 2 days before I discovered it, my corals had started shedding mucous, especially the large patch of Lettuce corals. Mushrooms all curled up small. I thought that it was because of a rather large water change I had done, but I always do and they never react whatsoever. I double checked the water when that happened but everything is perfect. ( I didn't check temperature because my RO system has always been a perfect temp as well). When all of this was happening, my older (13 years) Sailfin Tang started breathing very fast and stopped eating. He is normally a very aggressive eater. No other fish have shown any indication of having a problem, including a 16 yr old Engineer Goby and 3 Sailfin Mollies . Also a healthy assorted school of docile types of Damsels.

Its been about 5 days now. The Tang is finally appearing a little less stressed today. Still goes through its moody color changes dark or light, and no sign of disease. Still not eating though. Other fish are eating very well. After reading a bit online , I discovered that copper may be released into the tank and got a Hanna high copper tester. It tested at .32 ppm. I thought that was high and might be the reason the corals had suddenly shrunk. I put in 500 mg of Cuprisorb into a high flow hob box. Also large bag of carbon and treated with Prime every day since.

Mushrooms have opened up today back to almost normal. Kenyan Tree Corals have also expanded back to normal. Lettuce Corals still look pretty terriible, and a large Toadstool was pretty much melting during all of this. The end of it has turned upward and looks like a more normal color now, even though its entire trunk is still collapsed. I checked the bag of Cuprisorb for the telltale blue color , and its not showing any change from the new product.

So, does this mean that all of this was caused by the 110 volt power cord hanging in the water and I basically gave my sweet geriatric Tang an Arythmia ? Kinda kidding here but Im still at a loss. One more thing I noticed was the small patches of Algae on the 100 pounds of live rock has all died during all of this. Ive never been able to get rid of it before and the Tang always kept it controlled. I will have to scrub it off but holding off to not stress the Tang.

 

[Freenow54]

My tank water tests at 11.9v AC so I guess that's OK? (No ground probe running in the tank)

For the electricians out there, this is weird/curious:
GFCI that runs the tank -- I get 0.1v AC with ONLY one probe to ground and the other just in the air.
All other receptacles in the house that I tested that way (including 2 other GFCI) show 0.0v with just an occasional "-" (negative) on the meter, but still at 0.0v (so I guess VERY SLIGHT voltage but below the range of the meter).
*I do have a couple of those 3-light receptacle testers and they show CORRECT (wiring) on the GFCI receptacle I use for the tank.

'sup wit dat?

If pumps are shocking you, they're a problem. Are the korallias AC or DC?


That being said, a grounding probe is not a "better safe than sorry" device - a GFCI is. Is everything on your tank on a GFCI? If not, the grounding probe makes the tank significantly more dangerous. Grounding probes are designed to trip GFCIs sooner - the GFCI trips when the device starts to leak, rather than tripping when you stick your hand in.

If you've got a current leak, typically it's minor, because there's no clean path for electricity to travel to ground. You get shocked because you're a cleaner path to ground than the tank. With a grounding probe, if there's a leak, it's major, and its moving significant current through the tank all the time.

Grounding probes (without GFCIs) also enable the "Lighting fixture electrocution" hazard. Many reef fixtures are poorly isolated - and some are somewhat charged in normal use. With a grounding probe and no GFCI, brushing up against a bad/malfunctioning lighting fixture while working in the tank can mean you're a clean path to that grounding probe.

If pumps are shocking you, they're a problem. Are the korallias AC or DC?


That being said, a grounding probe is not a "better safe than sorry" device - a GFCI is. Is everything on your tank on a GFCI? If not, the grounding probe makes the tank significantly more dangerous. Grounding probes are designed to trip GFCIs sooner - the GFCI trips when the device starts to leak, rather than tripping when you stick your hand in.

If you've got a current leak, typically it's minor, because there's no clean path for electricity to travel to ground. You get shocked because you're a cleaner path to ground than the tank. With a grounding probe, if there's a leak, it's major, and its moving significant current through the tank all the time.

Grounding probes (without GFCIs) also enable the "Lighting fixture electrocution" hazard. Many reef fixtures are poorly isolated - and some are somewhat charged in normal use. With a grounding probe and no GFCI, brushing up against a bad/malfunctioning lighting fixture while working in the tank can mean you're a clean path to that grounding probe.

a GFI operates on amperage not voltage. I suppose maybe if a fish grounds itself it would die right away I would think since .1 of an amp kills. As another member said high voltage will as well because it has enough electrical presuure to seek ground and you or the fish is in the way. Dont know. Again I keep hearing the term ground probe . The devce alows the voltage to run through it and the unrestricted amperage trips the

breaker