Stray volts in aquariums

[Pete H]

Has anyone ever experienced or heard of stray electrical current or voltage in an aquarium from and exposed wired or a heater or other electrical source? Is it worth installing a grounding probe ? 

[Flumpweesel]

I had a cracked heater that caused stray current no idea how long it was in the tank it think it may have caused the loss of a rosy barb but they were new fish so hard to call.

I have had this happen once in over 30 years of fish keeping and the heater in question was over 10 years old.

I'm not sure a grounding probe would have reduced the risk to fish as it remained local to heater and the current would travel to the probe to be grounded.

I have never really looked into these though. 

[Pepere]

A ground probe is $13.00.

I have one in every tank.

and every tank is plugged into a Ground FaultCircuit Interrupting outlet (GCFI).

On the first of every month I trip and reset my GCFI.

I am an ABYC certified marine electrician and have taught Marine electrical safety courses.

 

so a GCFI outlet measures the current going out the hot lead and returning on the neutral lead. Rule number 1 in electricity is that all the Amps must come home.  Voltage drops across a load but the current stays the same…. If the GCFI circuit determines there is a mismatch exceeding 5 milliamps the circuit trips in under a tenth of a second.  
 

Here is the rub, it will only measure leakage if it is going someplace other than back on the neutral.  For that to happen, it has to have another place to go.  This is where the ground probe comes in to use.  It provides a different route for current to go to ground bypassing the neutral line.

Personally I would be happier having my GCFI outlet to trip before I stick my hands in the water. That is why I think a ground probe is cheap insurance.

Tripping the GCFI outlet on the first of the month ensures the tripping mechanism physically works and is not stuck. The exercising of it also prevents sticking. Current GCFI outlets also conducts an internal check when resetting the outlet and will not reset if it determines there is a problem.

GCFI outlets are a great safety device and a ground probe in your aquarium works with it.

having said that, all of my devices that have electrical cords in the water, ie heaters, powerheads, hob filters etc are plugged in to a single power strip. I try to always remember to flip the power off on that strip before sticking my hands or tools into the water. And of course that means I have to try to remember to turn it back on as soon as I am done.

And as I always told students in  any of my classes.  Never ever go swimming anywhere near a freshwater marina.  And avoid swimming near saltwater marinas too, but they are not as dangerous as freshwater marinas.

 

 

 

[Scapexghost]

It would be the current that is the issue not voltage. Think of voltage as height and current as falling.

Something i've heard about but not experienced

[Odd Duck]

Back in the day we had metal frame tanks and very poorly wired, poorly grounded (usually not grounded at all) lights in metal hoods, and heaters that could not be fully submersed that inevitably got water in them.  It was a dicey thing whether you were going to get a little tingle if your arm touched the metal frame during any given water change.  Then we learned about using grounding probes and life was better if not as tingly.  Then equipment got safer and we kind of forgot about grounding plugs.

Then I had this same discussion about grounding probes just the other day with @Pepere and it’s made me think twice about it all again.

I have a quite a few tanks.  Not record setting or anything, but probably more than I ought to have.  😆  I don’t have heaters or other electrics in all of them and hope to eventually have heaters in fewer of them once I’m consolidated into a fish room.  But I’m thinking I need to get some grounding probes in some tanks.  I haven’t gotten any tingles but I’m not the slightest bit interested in finding a little too much juice in a tank someday.

[Anjum]

On 9/23/2022 at 6:01 PM, Pepere said:

A ground probe is $13.00.

I have one in every tank.

If you'd be so kind, explain this to me like I'm a 3 year old... I've always had the hardest time understanding electricity.

Where exactly is the grounding probe? What is it attached to? 

I have all the stuff in my tanks plugged into GFCI strips, my husband had the foresight to insist on that. But the stray current in the water thing worries me.. 

[Streetwise]

I found this Neptune Apex thread:

https://forum.neptunesystems.com/showthread.php?24881-Stray-Voltage-Detection

[Fish Folk]

I get stray current once every year or so. Cheap lighting setup is typically my cause. Occasionally it is due to a cracked heater or an old HOB. I try to buy titanium heaters now to avoid that.

There is some experimental question whether the fish are affected much or not. Current will find the path of least resistance. I’m not convinced this necessarily leads “through fish.” Typically, I feel current because it is going _through me_.

But since I dislike that feeling… I always find and fix the problem ASAP!!!

Edited September 25, 2022 by Fish Folk

[Pepere]

On 9/24/2022 at 8:21 PM, Anjum said:

f you'd be so kind, explain this to me like I'm a 3 year old... I've always had the hardest time understanding electricity.

Well, I have experience explaining things to a three year old since I watch my 3 year old grandson every weekday so Mommy and Daddy can work…

 

I think though we can elevate the discussion beyond that and still be safe.

 

I buy a Titanium ground probe from a well known retailer for about $13.00.  A simple internet search will find it easily enough.  It has a short rod of Titanium attached to a cord that you secure low in your tank preferably close to your elctrical items in the tank held in place with a suction cup.

 

the other end of the cord plugs into an outlet with a ground. (The third round hole below the two slots.

not all grounded outlets however are in fact grounded. Itwill do no good if it isnt.  
 

a low cost outlet tester such as below can be plugged into your outlet to be sure a ground is present and the outlet is wired correctly.

 

https://www.guitarcenter.com/American-Recorder-Technologies/Ground-Fault-Outlet-Receptacle-Tester-110V-1273887987114.gc?cntry=us&source=4WWRWXMP&msclkid=fe0fd1569ac718d06bafb2793c830298&utm_source=bing&utm_medium=cpc&utm_campaign=**LP - Shop - Pro Audio - Signal Processors&utm_term=4577954171838117&utm_content=1273887987114 | American Recorder Technologies Ground Fault Outlet Receptacle Tester 110V | %244.99 USD

 

it sort of ensures everything is correct, though, as it can not detect of the ground is a “bootleg ground”…

 

some older homes had 2 conductor wire only with no grounds.  Code allows a GCFI outlet to be the first outlet in the circuit and have it protect all the outlets down stream but there is no equipment ground. If this is the case the tester above will tell you there. Is no ground.  Plugging a ground probe into an outlet that does not have a ground wont help you any.

 

GCFI outlets are good and “should” trip if your arm is in the water, current is leaking into the water, and your body comes into contact with a ground source.  My preference though is for the GCFI to trip before I stick my hands in, and that is what a ground probe can do for you.

 

my very strong preference is to have my tanks protected by having both a GCFI outlet and a ground probe..

 

did this help?

[Pepere]

On 9/24/2022 at 8:47 PM, Fish Folk said:

Typically, I feel current because it is going _through me_.

Just so that you know, the threshold at which you can “feel a tingle” is not a whole lot lower than the threshold of current that can put your heart into ventricular fibrilation.

 

I used to be a Paramedic earlier in my life than getting my Marine Electrician credentials.  Going in to Vfib is never a good day for anyone.

iIf you feel tingles from time to time, you really really ought to have a GCFI outlet and a grounding probe.

If you dont want to feel tingles from time to time you really really ought to have a GCFI outlet and a grounding probe.

[Anjum]

On 9/24/2022 at 6:00 PM, Pepere said:

did this help?

I'll have to read through it a few times 😅 But I'll have hubs read it too, he'll get it better than me. He already said he can switch out the outlets for GFCI pretty easily. The wiring in this (old) house has surprised him more than once, so he also can, or already has, verified that things are grounded properly etc.

Thank you very much for writing it all out! I think this will be a valuable thread to refer back to. 

Edited September 25, 2022 by Anjum

[Tanked]

On 9/23/2022 at 9:01 PM, Pepere said:

A ground probe is $13.00.

I have one in every tank.

and every tank is plugged into a Ground FaultCircuit Interrupting outlet (GCFI).

On the first of every month I trip and reset my GCFI.

I am an ABYC certified marine electrician and have taught Marine electrical safety courses.

 

so a GCFI outlet measures the current going out the hot lead and returning on the neutral lead. Rule number 1 in electricity is that all the Amps must come home.  Voltage drops across a load but the current stays the same…. If the GCFI circuit determines there is a mismatch exceeding 5 milliamps the circuit trips in under a tenth of a second.  
 

Here is the rub, it will only measure leakage if it is going someplace other than back on the neutral.  For that to happen, it has to have another place to go.  This is where the ground probe comes in to use.  It provides a different route for current to go to ground bypassing the neutral line.

Personally I would be happier having my GCFI outlet to trip before I stick my hands in the water. That is why I think a ground probe is cheap insurance.

Tripping the GCFI outlet on the first of the month ensures the tripping mechanism physically works and is not stuck. The exercising of it also prevents sticking. Current GCFI outlets also conducts an internal check when resetting the outlet and will not reset if it determines there is a problem.

GCFI outlets are a great safety device and a ground probe in your aquarium works with it.

having said that, all of my devices that have electrical cords in the water, ie heaters, powerheads, hob filters etc are plugged in to a single power strip. I try to always remember to flip the power off on that strip before sticking my hands or tools into the water. And of course that means I have to try to remember to turn it back on as soon as I am done.

And as I always told students in  any of my classes.  Never ever go swimming anywhere near a freshwater marina.  And avoid swimming near saltwater marinas too, but they are not as dangerous as freshwater marinas.

 

 

 

A google search for titanium ground probe proved fruitful. I did not know they existed.  Having gotten "the tingle" from pond/fountain pumps, and also living in an older home where a 3 prong plug may not actually be grounded (or worse), this is good advice.  A  $5. receptacle tester should be in everyone's tool box especially if you do your own electrical/DIY projects.

[Pepere]

I have learned to never ever trust anything is wired correctly until I check it myself….

 

i have run across hot ground wires, hot neutral reversed, outlets powered by a different panel than they were supposed to be, 240 run into a standard duplex outlet…

 

there are people with really interesting ideas out there….

if you go camping and get a water, electric site, do yourself a favor and test the oulet before plugging in to it…

[Wrencher_Scott]

On 9/23/2022 at 6:01 PM, Pepere said:

A ground probe is $13.00.

I have one in every tank.

and every tank is plugged into a Ground FaultCircuit Interrupting outlet (GCFI).

On the first of every month I trip and reset my GCFI.

I am an ABYC certified marine electrician and have taught Marine electrical safety courses.

 

so a GCFI outlet measures the current going out the hot lead and returning on the neutral lead. Rule number 1 in electricity is that all the Amps must come home.  Voltage drops across a load but the current stays the same…. If the GCFI circuit determines there is a mismatch exceeding 5 milliamps the circuit trips in under a tenth of a second.  
 

Here is the rub, it will only measure leakage if it is going someplace other than back on the neutral.  For that to happen, it has to have another place to go.  This is where the ground probe comes in to use.  It provides a different route for current to go to ground bypassing the neutral line.

Personally I would be happier having my GCFI outlet to trip before I stick my hands in the water. That is why I think a ground probe is cheap insurance.

Tripping the GCFI outlet on the first of the month ensures the tripping mechanism physically works and is not stuck. The exercising of it also prevents sticking. Current GCFI outlets also conducts an internal check when resetting the outlet and will not reset if it determines there is a problem.

GCFI outlets are a great safety device and a ground probe in your aquarium works with it.

having said that, all of my devices that have electrical cords in the water, ie heaters, powerheads, hob filters etc are plugged in to a single power strip. I try to always remember to flip the power off on that strip before sticking my hands or tools into the water. And of course that means I have to try to remember to turn it back on as soon as I am done.

And as I always told students in  any of my classes.  Never ever go swimming anywhere near a freshwater marina.  And avoid swimming near saltwater marinas too, but they are not as dangerous as freshwater marinas.

 

 

 

GFCI with a ground in the water is a good idea.

I don't think I would worry much about sticking my hands in the tank, unless I'm holding onto a water pipe or standing in a puddle. 🙂

Can you explain the dangers of swimming in marinas? 

Thanks.

[Pepere]

On 9/26/2022 at 11:58 AM, Wrencher_Scott said:

I don't think I would worry much about sticking my hands in the tank, unless I'm holding onto a water pipe or standing in a puddle. 🙂

Can you explain the dangers of swimming in marinas? 

You can safely hold on to very high voltages with no problem at all so long as that is the only voltage potential you are in contact with.  As you mention so long as you don’t have contact with ground potential.  I dont know about you, but when I am involved in a task, I can become a bit oblivious to other things.   It is way too easy to inadvertently come in contact…. Master electricians working hot make mistakes and die from it.

if the power is switched off you are safer than having it on.

As Mister Miagi told Danielsan,,”The best block is the dont be there block.”

 

Murphy is a very busy fellow. Shutting off the power to anything that has a power cord going in to the water is better than depending on the integrity of seals and insulation on the wires and the GCFI outlet working properly.

Think of your GCFI as a safety belt.  Still better to avoid the crash anytime you can…

and a GCFI outlet is a great safeth device but it is not foolproof.  If electricity comes out the hot, goes through your body and back through the neutral it wont trip, but it might well kill you.

Two hands in opposite sides of a freshwater tank could do it…

 

This is the same issue with freshwater marinas.  Marinas have wiring on moving docks near water.  Connected up in the spring left there for 5-6 months taken apart and typically exposed to weather all winter….  Not to mention boats are hooked up in all sorts of disrepair.  The saying is that the only thing that reliably works on an old boat is the owner… And if you think there are sketchy things with household wiring, you should look into boat wiring….

 

in any event boats typically have large underwater pieces of metal that are bonded to the electrical ground point.  In fact they really should have it is part of federal code…

Statistical probability is that there will be boats in every Marina that will be leaking current into the water.  Why is freshwater more of a hazard?  In saltwater the saltwater dissipates the charge to ground easily.  Freshwater not so much.  As such you have waves of potential voltages.  As you swim through those waves your body can be between voltage potentials and your body has a whole lot more electrolyte in it than the surrounding water.  The current shorts through your body to the lower potential.  And it need not be a high enough current to do any cellular damage or put your heart in to v fib.  It can be below 75 milliamps and simply paralyze you so you cant stay above the water…

Autopsy would reveal you died by drowning, but the electrical leakage caused you to drown.Saltwater Marinas are not the same risk, but I am not jumping off the dock into the water there either….

There are old electricians and there are bold electricians, but there are not many Old Bold electricians…

Edited September 26, 2022 by Pepere

[Anjum]

@Pepere so funny story... when I initially asked my husband if he had one of those ground testers, he said no but assured me everything was grounded, he'd already checked. Well he had to go to the hardware store the next day, and whaddya know, he comes home with one 😅 He gets to testing all the outlets & come to find out, there's a whole wall in our kitchen where the outlets aren't grounded! He was not happy about that. I told him sorry I found you another electrical mystery to solve. 

But I was also thinking about this whole issue of potential stray current in a tank... and I understand that having the ground probe would eliminate (or reduce?) any stray current in the water. But, you wouldn't know this is happening, correct? It would be making the tank safe for the fish, etc, but I wouldn't know I was having an equipment malfunction. I guess that's what I want to know - Is there a way to be alerted to the fact there's stray current in the tank? 

[Pepere]

On 9/26/2022 at 6:26 PM, Anjum said:

But I was also thinking about this whole issue of potential stray current in a tank... and I understand that having the ground probe would eliminate (or reduce?) any stray current in the water. But, you wouldn't know this is happening, correct? It would be making the tank safe for the fish, etc, but I wouldn't know I was having an equipment malfunction. I guess that's what I want to know - Is there a way to be alerted to the fact there's stray current in the tank? 

Combining the ground probe with a working GCFI outlet will cause the outlet to trip if current exceeding 5 milliamps of current. Letting you know you have a ground fault. 
 

tripping and resetting your GCFI every month is a very good practice that very very few people do.  I reccomend doing it on the first of the month every month.

 

if your GCFI ever trips you need to determine why it is tripping.  Dont ignore it.

Now Ghost trips are possible, ie a trip without a ground fault. It could be a tired GCFI outlet and it could be cumulative capacitance over the circuit.

I had an electrician friend of mine install an outside outlet for a tenant who has an electric car.  All new install with top line parts.  (My certification is only for marine work, not residential)

The car was frequently ghost tripping the GCFI.  No ground fault with the car was detected…  we finally solved it by using a different brand of GCFI also a very well respected brand…

can you determine ifthe ground probe is draining current without tripping a GCFI?  Yes.  You can get a multimeter with a clamp on feature that you would clamp the ring around the ground probe wire and set the multimeter to register milliamperage, or if no gcfi you can also check for greater current.

what many people do not realize is that both alternating current and direct current can travel at the same time on the same conductor which can also be confusing…

 

as to the dropped ground on outlets in the kitchen, it is very understandable. Likely they are all on the same circuit. Typically, a ground wire comes into one box and it daisy chains to all of the outlets on the circuit.  Typically whoever does the wiring attaches the two ground wires together with a third wire attaching that to the ground connection on the outlet. The three wire are then either wire nutted or crimped with a ground crimp. The bundle is then pushed into the box.  It is easy enough for one of those wires to get  loose from the others and hence you have a “dropped ground” to everything downstream.  It is also possible the ground wire disconnected in the electrical panel itself, or broke…

if this happened with a hot or neutral wire you would know instantly as the outlets would not work.  The only way to know if you have a “dropped ground” is to test for it…