Stray voltage in a localized area of tank

[Nordy]

Two days ago after taking out my return pump for its first cleaning and putting it back in the sump cleaned, I put my hand in the top right corner of my tank to reposition a gyre. I noticed an open cut on my hand under the water was sensing electricity in the water. Over the next hour with my hand in the water, I would get zapped intermittently. The shock would come and go. Without testing anything with a volt meter, I thought it was a probe or optical sensor from my apex unit. I took all that stuff out.
Today I did a water change and felt the electrical shock again, same area. I had moved my voltage probe earlier to the general area, and after touching that voltage probe, I took It out because it seemed like the source of the shock I was feeling. Could this be? Or is it a place voltage is being attracted into? The voltage probe is in a gfci 20 amp outlet I had an electrician install for the tank. I have been swamped and have zero time for figuring this out. Tomorrow I’ll buy a volt meter, turn off all equipment, and test one thing at a time. My understanding of using the volt meter would be to have one of the probes, (not sure negative or positive) on the equipment and one in the water column, looking at the meter readout. Tomorrow I can make time for this after work. Please help, this is a headache and not in area I understand. If you guys can, please give me a thorough rundown for dummies on exactly what I have to do.

 

[mann1139]

You have the right steps.

Turn off all electrical items that enter the tank. I also check anything close, as I got shocked from a 'salt path' of wet salt once.

Examine the items and cords, look for damage.

Multimeter should be set for ac voltage. One end in tank, one end at ground.

Turn them on one at a time, watch for voltage.

 

[Nordy]

Figured it out kinda. So all electrical equipment in the tank were setting off the voltage meter reading upon testing. Then we took an extension cord and used a completely different outlet. No stray voltage. The outlet putting stray voltage from all equipment was a gfci outlet installed by an electrician. My dad said maybe the ground is faulty?? Anyways, I have an electrician coming to look at it on the 21st of this month. My tank sits 5 inches out from the outlet and is a foot behind the tank. Just hoping the electrician can get the job done without saying this large reef tank needs to be moved. Lost a few fish and welks in my tank have been feasting on some other invertebrates. Kinda ticked by all this, but I think my heater that overheated in my first tank 6 years ago was worse. Hopefully back on course with no more headaches soon.

 

[BeanAnimal]

There are so many misunderstanding here that I am not sure where to begin.

First of all. Is all of the tank equipment plugged into the GFCI? Or at least was it yesterday?

 

[A_Blind_Reefer]

There are so many misunderstanding here that I am not sure where to begin.

First of all. Is all of the tank equipment plugged into the GFCI? Or at least was it yesterday?

I just like the process,,,felt shocked when everything was plugged into a gfci protected outlet…hold my beer, let me unplug that and use a non-protected outlet…

Unless I am misunderstanding which happens

 

[ZoWhat]

Hate to see you pay the first $150 for an Electrician to Just walk thru your front door.... when you only have a faulty device.

Electrical circuits are sealed in glass in aquarium devices (pumps, powerheads, heaters).

Reverse engineer any "in-water" device and you'll find a block of green glass protecting the electrical connections

The glass over time gets micro-cracks.

The intermittent minor shocks you are feeling is when a circuit is created thru the micro-cracks. It comes and goes with the heat of expansion

Stray current will just get worse over time.

Either replace the piece of equipment by plugging in one device at a time until you feel the voltage. IDing the offending device....

Or monitor the fish for sudden changes in direction swimming as a group. Tangs tend to change direction sharply and then immediately hide in rockwork

If voltage effecting fish, definitely time to ID and replace the device

 

[Nordy]

There are so many misunderstanding here that I am not sure where to begin.

First of all. Is all of the tank equipment plugged into the GFCI? Or at least was it yesterday?

All equipment was plugged into surge protector outlets, and the surge protectors were plugged into the GFCI.

 

[Nordy]

Hate to see you pay the first $150 for an Electrician to Just walk thru your front door.... when you only have a faulty device.

Electrical circuits are sealed in glass in aquarium devices (pumps, powerheads, heaters).

Reverse engineer any "in-water" device and you'll find a block of green glass protecting the electrical connections

The glass over time gets micro-cracks.

The intermittent minor shocks you are feeling is when a circuit is created thru the micro-cracks. It comes and goes with the heat of expansion

Stray current will just get worse over time.

Either replace the piece of equipment by plugging in one device at a time until you feel the voltage. IDing the offending device....

Or monitor the fish for sudden changes in direction swimming as a group. Tangs tend to change direction sharply and then immediately hide in rockwork

If voltage effecting fish, definitely time to ID and replace the device

No stray voltage was measured after taking them out of the GFCI outlet, and using a completely different outlet to power everything. All but one fish have resumed there normal range throughout the tank.

 

[ShakeyGizzard]

Thats funny, believe it or not, the safest place to be outside during an electrical storm is in the pool not touching the bottom. The water is a better conductor than your body. When you touched the probe, the water now conducted through your body. No matter how you do it. adding a toaster to your tank will result in stray voltage

 

[BeanAnimal]

All equipment was plugged into surge protector outlets, and the surge protectors were plugged into the GFCI.

Thank you for answering.

The tingle you felt was induced voltage exciting the raw skin in your cut. If it were actual fault current from a device, it would have caused the GFCi to trip when you put your hand in the water.

Moreover, you said that you have a ground probe in the tank. If there was fault current, this would have tripped the GFCI before you put your hand in the tank,

Plug everything back into the GFCI please.

 

[ShakeyGizzard]

Magnestic fields produced by wave makers pumps will induce voltage into the water, especially since we maintain iron and magnesium levels in the water

 

[BeanAnimal]

No stray voltage was measured after taking them out of the GFCI outlet, and using a completely different outlet to power everything. All but one fish have resumed there normal range throughout the tank.

There is no such thing as “stray voltage”. You either have a fault or induced voltage. If there is a path to lower potential (ground) there is current flow.

The GFCI trips if that current is fault current (leaking from a device). If it is induced voltage, in the case of your tank it is not dangerous and can’t reliable be read with a meter in the manner in which you (and every other aquarist) try to read it.

 

[ShakeyGizzard]

the fish cant feel it, unless the are touching the path back to a ground.

 

[ShakeyGizzard]

I'm out, to much beer here, later folks

 

[BeanAnimal]

Electrical circuits are sealed in glass in aquarium devices (pumps, powerheads, heaters).

Maybe epoxy, but not glass.

Stray current will just get worse over time.

If there was a faulting device, the GFCI would have tripped due to the ground probe and/or has hand in the water.

 

[A_Blind_Reefer]

….everyone back in the pool, Lightning’s coming! Do not get out of the pool!

 

[BeanAnimal]

….everyone back in the pool, Lightning’s coming! Do not get out of the pool!

I got the living snot knocked out of me by a faulting pool light one time. Touched the metal trim and got whacked hard. May have peed the pool.

 

[A_Blind_Reefer]

I got the living snot knocked out of me by a faulting pool light one time. Touched the metal trim and got whacked hard. May have peed the pool.

I now have my excuse for the next time I per in the pool! Ha

Funny now, not then I’m sure

 

[PharmrJohn]

I got the living snot knocked out of me by a faulting pool light one time. Touched the metal trim and got whacked hard. May have peed the pool.

That got me laughing!

 

[BeanAnimal]

I now have my excuse for the next time I per in the pool! Ha

Funny now, not then I’m sure

It was easily 30+ years ago and I haven’t gone anywhere near an underwater pool light since. No joke. Been shocked by a lot of things over the years… even 575 DC trolly wire and 277 a few times and a fly back transformer from an old TV, etc … but that one was one to remember. It was as if my whole body got hit by a hammer. I mean like Thor’s hammer…