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I’ve used my body to trip a gfi twice now. Very unpleasant, but probably saved my life.Why is it that some people refuse to put a grounding probe in their aquarium? I've seen many arguments against using them, some of which are based on what I believe to be bad information. I want to make the case for why every aquarium should have a grounding probe installed.
We have these beautiful aquariums full of salt water into which we place electrically operated equipment. Everyone has heard the phrase "Water and electricity don't mix" and it is especially true of salt water. Yet this doesn't have to be dangerous and a ground probe is key to making this safe.
An electrical shock occurs when current flows through a person. There are three main factors that impact the severity of the shock. The amount of current flowing through the person, the length of time they are being shocked, and the path the current takes through the body. For a shock to occur a person must be touching an energized conductor and a source to ground. The glass and acrylic most aquariums are made from are excellent insulators. If a pump or heater develops a fault in the salt water, it will raise all of the water in the aquarium to the same voltage as is available at the fault, typically close to 115V. If you are touching the metal housing of a light fixture or standing on wet concrete and touch the water, you become the best path for the current to take to get to ground. These shocks are most likely to take the most dangerous path, which is through our heart. It will go into the hand, through the heart, and either out the opposite hand or down through our legs. This is one way the ground probe keeps us safe. Electricity always takes the lowest resistance path to ground. The human body does have some resistance so a properly maintained ground plug will always offer a lower resistance path to ground.
I would also make the argument that the use of a ground plug is important to the health of our marine fish, but not because of a risk of electrical shock. Scientists use electro-fishing techniques to collect or count fish populations by shocking fish. Electric eels hunt prey by shocking them with electricity. So why do I say marine fish are not at risk for being shocked? They live in salt water. Electric eels are a fresh water species and electro-fishing only works fresh water. In a fresh water environment the fish is more conductive than the water just like people are more conductive than air. You cannot shock a marine fish while it is in salt water since the water is more conductive than the fish. This doesn't mean that marine fish aren't affected by electricity.
It is a generalization to say that all of the salt water is at the same voltage in our aquariums. In reality, small differences in potential can exist within the water. Eddy currents of water will cause a difference in voltage. There will be a difference in potential caused by any air bubbles that may touch a fish. While these may not cause shocks, it can cause a serious irritation across the surface of the fish. I would also point out that you do not need to have an electrical fault to have a harmful voltage in your aquarium. Any energized cord either running in the water or along the outside of the tank will create a voltage in the tank using a process called induction. This is why many people see a voltage in their aquariums without having a GFCI breaker trip. A ground probe will prevent any voltage from building up in the aquarium water, protecting our fish from these small voltage differences.
Grounding probes also protect our tank from another problem that is much harder to see and correct. If you have an electrical fault in your tank, there is a high probability that you have exposed copper in your system. This copper will corrode in salt water and the corrosion is accelerated when impacted by electricity. Even if you use a GFCI, the circuit will not trip on a fault until you have a source to ground. A ground probe will immediately provide that path to ground. If you do not have a ground probe installed, you could be leaching copper into your system for days or longer until a path to ground from your water is established.
The one argument against using ground probes I cannot counter is that it could provide a heat source during an electrical fault. If you have an electrical fault in a very narrow resistance range, and do not use GFCI protection, it can act like a heater. I know I wouldn't risk the safety of my family and friends in an effort to avoid this one scenario. I hope after reading this you won't either.
I have tripped a GFI two different times with my body as ground. It is very unpleasant. A ground probe properly installed should help trip the GFI before I do.Why is it that some people refuse to put a grounding probe in their aquarium? I've seen many arguments against using them, some of which are based on what I believe to be bad information. I want to make the case for why every aquarium should have a grounding probe installed.
We have these beautiful aquariums full of salt water into which we place electrically operated equipment. Everyone has heard the phrase "Water and electricity don't mix" and it is especially true of salt water. Yet this doesn't have to be dangerous and a ground probe is key to making this safe.
An electrical shock occurs when current flows through a person. There are three main factors that impact the severity of the shock. The amount of current flowing through the person, the length of time they are being shocked, and the path the current takes through the body. For a shock to occur a person must be touching an energized conductor and a source to ground. The glass and acrylic most aquariums are made from are excellent insulators. If a pump or heater develops a fault in the salt water, it will raise all of the water in the aquarium to the same voltage as is available at the fault, typically close to 115V. If you are touching the metal housing of a light fixture or standing on wet concrete and touch the water, you become the best path for the current to take to get to ground. These shocks are most likely to take the most dangerous path, which is through our heart. It will go into the hand, through the heart, and either out the opposite hand or down through our legs. This is one way the ground probe keeps us safe. Electricity always takes the lowest resistance path to ground. The human body does have some resistance so a properly maintained ground plug will always offer a lower resistance path to ground.
I would also make the argument that the use of a ground plug is important to the health of our marine fish, but not because of a risk of electrical shock. Scientists use electro-fishing techniques to collect or count fish populations by shocking fish. Electric eels hunt prey by shocking them with electricity. So why do I say marine fish are not at risk for being shocked? They live in salt water. Electric eels are a fresh water species and electro-fishing only works fresh water. In a fresh water environment the fish is more conductive than the water just like people are more conductive than air. You cannot shock a marine fish while it is in salt water since the water is more conductive than the fish. This doesn't mean that marine fish aren't affected by electricity.
It is a generalization to say that all of the salt water is at the same voltage in our aquariums. In reality, small differences in potential can exist within the water. Eddy currents of water will cause a difference in voltage. There will be a difference in potential caused by any air bubbles that may touch a fish. While these may not cause shocks, it can cause a serious irritation across the surface of the fish. I would also point out that you do not need to have an electrical fault to have a harmful voltage in your aquarium. Any energized cord either running in the water or along the outside of the tank will create a voltage in the tank using a process called induction. This is why many people see a voltage in their aquariums without having a GFCI breaker trip. A ground probe will prevent any voltage from building up in the aquarium water, protecting our fish from these small voltage differences.
Grounding probes also protect our tank from another problem that is much harder to see and correct. If you have an electrical fault in your tank, there is a high probability that you have exposed copper in your system. This copper will corrode in salt water and the corrosion is accelerated when impacted by electricity. Even if you use a GFCI, the circuit will not trip on a fault until you have a source to ground. A ground probe will immediately provide that path to ground. If you do not have a ground probe installed, you could be leaching copper into your system for days or longer until a path to ground from your water is established.
The one argument against using ground probes I cannot counter is that it could provide a heat source during an electrical fault. If you have an electrical fault in a very narrow resistance range, and do not use GFCI protection, it can act like a heater. I know I wouldn't risk the safety of my family and friends in an effort to avoid this one scenario. I hope after reading this you won't either.
I don't see how it could. A GFCI compares the power leaving the hot side to the power returning to the neutral. If there is a difference, then it trips the GFCI.I tried reading through the thread but having a hard time coming to a conclusion on this.
My house is new and they used GFCI circuit breakers... the breakers themselves . These exact breakers to be specific.
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Does this act like having a GFCI outlet alongside my ground probe? Or should i still have a GFCI outlet on top of the GFCI circuit breaker.
Yes, It's dual function. No need for a gfci receptacle behind it. If it was afci only then you would need a gfci receptacle as well. As a 27 year electrician, the afci, gfci thing is getting out of hand. They're more hassle then they're worth in my opinion.I tried reading through the thread but having a hard time coming to a conclusion on this.
My house is new and they used GFCI circuit breakers... the breakers themselves . These exact breakers to be specific.
![]()
Does this act like having a GFCI outlet alongside my ground probe? Or should i still have a GFCI outlet on top of the GFCI circuit breaker.
Yes, It's dual function. No need for a gfci receptacle behind it. If it was afci only then you would need a gfci receptacle as well. As a 27 year electrician, the afci, gfci thing is getting out of hand. They're more hassle then they're worth in my opinion.
Hello Brew12, You have answered a LOT of questions in this thread. Pretty awesome.
GFCI is not required in all rooms in your house.Powers2001, Everyone changes fuses to circuit breakers, I also did in my house.
But it won't make anything safer unless you need or want to use a GFI which are now required almost everywhere which I feel is a mistake.
In my new home here on eastern Long Island every circuit was on a GFI breaker but there is a thing called being to safe.
On some very big construction jobs we sometimes spent so much time and money on safety that we hardly worked actually building the building.
Of course we want to be safe, but we also want to get the job done so it is a trade off. I want GFCIs (or GFIs as they are called in the trade) where they are needed, which is anywhere near water.
But I don't want them on my living room, bedroom or even my outside outlets. The outside outlets are of course dangerous and the code requires that they be installed there. But the people who wrote the code were not necessarily electricians or home owners and if you install Christmas Lights, they will trip constantly. :cool: Especially if, like me, you live by the sea which is very damp and the things don't want to stay on.
I removed most of them in my house except where I feel they are needed. But thats just me. You should leave them installed to be very safe or if you have small kids or a fish tank.
I once had to change the very large fuses, dozens of them (5,000 amps I think) in a New York city garbage incinerator for GFI breakers which were as large as a Volkswagen and a crane was permanently installed on the panels to crank out those breakers.
To turn on those breakers you had to use a big crank, crank them up, then push a button and stand back as the thing banged on. :oops: The incinerator had it's own powerplant to power it.
This bottom picture is that incinerator. I am CAD welding a ground cable here. The top picture is the roof of the Plaza Hotel where I installed the lights to light up the top of the place.
I used some of those spare lights on my reef tank.
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Reference to ground has nothing to do with GFCI operation. GFCI's measure current between the hot and the neutral and is the reason ungrounded circuits can use GFCI for compliance.I’ve used my body to trip a gfi twice now. Very unpleasant, but probably saved my life.
I have tripped a GFI two different times with my body as ground. It is very unpleasant. A ground probe properly installed should help trip the GFI before I do.
That is a combination GFCI and AFCI. While I'm not sure what your local code requires it is only AFCI that is required lately on all residential circuits.I tried reading through the thread but having a hard time coming to a conclusion on this.
My house is new and they used GFCI circuit breakers... the breakers themselves . These exact breakers to be specific.
![]()
Does this act like having a GFCI outlet alongside my ground probe? Or should i still have a GFCI outlet on top of the GFCI circuit breaker.
A GFCI does not take the grounding conductor (EGC) into account. It measures current between the hot and the neutral. GFCI works with or without grounded circuits.I don't see how it could. A GFCI compares the power leaving the hot side to the power returning to the neutral. If there is a difference, then it trips the GFCI.
I don't see how this monitors the neutral because it doesn't have a pigtail.
You can install GFCI receptacles and then plug anything you want into them. This protects anything plugged into the GFCI receptacle.Hello Brew12, You have answered a LOT of questions in this thread. Pretty awesome.
I'm going to ask another. It may have been asked and I missed it somewhere. I looked at your thread on wiring the GFCI outlets and plugging them into the wall. If I understood correctly, you had done this and plugged them into your APEX.
Could I do this with a couple of CFCI outlets and plug them into a power strip? Wondering if I could wire a GFCI to plug into each outlet of a power strip to make it protected, and at the same time, not having everything on the same GFCI so I won't lose all equipment in the case of one tripping.
Thanks!
I didn't say it did. It was a long time ago, but I believe that the post was about a regular breaker with no connection to neutral.A GFCI does not take the grounding conductor (EGC) into account. It measures current between the hot and the neutral. GFCI works with or without grounded circuits.
This breaker plugs directly to the neutral bus. No pigtail required
I was responding to the picture in the thread. Its a combination GFCI and AFCI. No pigtail required. The poster asked about it.I didn't say it did. It was a long time ago, but I believe that the post was about a regular breaker with no connection to neutral.
You have to admit that GFCI is much more effective with a ground connection. It makes it easier to detect "leakage" when the current has somewhere to go.
I retired about 15 years ago and I know at that time you were only allowed to have 10 receptacles on a circuit.. This is US code. In Canada and other countries, there are limits as to how many receptacles can be on one circuit.
I'm just an electrical engineer, I'm not going to argue.I was responding to the picture in the thread. Its a combination GFCI and AFCI. No pigtail required. The poster asked about it.
I can't admit to something that is wrong. GFCI receptacles do not require a ground to work. So the ground has no influence on its operation. This is the reason ungrounded circuits can be made compliant with the use of GFCI.
Electricity is not looking for a path to ground nor does it follow the path of least resistance.
Electricity is always looking for a path to its source. In your situation it would be the transformer that supplies your dwelling.
Google these things and see. Theres to much opinion on electricity and how it works.
That's a lot of outlets!!!I retired about 15 years ago and I know at that time you were only allowed to have 10 receptacles on a circuit.
Maybe they changed it now.
You should see how many I have in my workshop/ man cave/ fishroom. :rolleyes:That's a lot of outlets!!!