Grounding probe or No grounding probe

[Brew12]

I beg to differ. While that 5mA is swimming around the tank or following some other path it's not returning on the neutral. As I said a GFCI monitors for an imbalance between the hot and the neutral it doesnt care were that current is, only that its not where it's supposed to be. I've only been an inside wireman for 12 years.

If a gfci device doesnt trip it is either wired incorrectly or it's a faulty piece of equipment.

I'm not sure why you think the 5mA is "swimming around the tank". Think of the tank as an extension of the electrical insulation of the hot wire. The hot wire has voltage well past the GFCI that hasn't made it to the neutral. By your theory, that should trip the GFCI.
Voltage, with no path for current flow, will not trip a GFCI. The tank can be energized with no current flow just like the conductor wire.

Not that it matters, but I worked as a submarine electrician for 10 years with the final 3 1/2 teaching electrical theory. I'm now on my 18th year as an electrical engineer. You can believe me or not, that is up to you. My feelings won't be hurt either way.

 

[Kraaken]

Its an easy test and yes I have done it. Take a bad power head and to make it worse nick the hot wire next to the pump and drop it into a bucket of water, pick one, salt or fresh. Plug the pump into a new GFCI receptacle. DO NOT STICK YOUR HAND IN THE BUCKET! When it doesn't trip drop a grounding probe in. I used a 10 gallon tank for our local fish club with a glass lid to make sure no one put their hand in to show others how dangerous water and electricity can become. That was one of the dumbest test I did when I was young and dumb. It hurt like hell being barefoot and on a tile floor. Guess what? The GFCI didn't trip when I got shocked, it did when I dropped the grounding probe in.

 

[Kraaken]

When you were younger huh? That speaks volumes. Older GFCI receptacles would still work when wired backwards but offer no GFCI protection. Newer GFCI receptacles simply wont work. When wiring a gfci receptacle there is a line side and a load side which is why you trace your circuit out to make sure which side is the line.

If a gfci Is wired correctly and doesnt trip it's a faulty gfci. Electrical devices such as receptacles, switches, breakers etc. do go bad over time which leads to whole other can of worms which are spec grade devices. They cost more but but they will last longer.

I'm not knocking ground probes. Sounds like they add an extra layer of protection but as an Inside Wireman if I had to chose between one or the other... GFCI hands down. I know the general idea is that electricity takes the path of least resistance.... nope. It takes all paths which is why I want the circuit killed in the event of a fault instead having a current hanging around looking for a reference to ground.

 

[Kraaken]

I'm not sure why you think the 5mA is "swimming around the tank". Think of the tank as an extension of the electrical insulation of the hot wire. The hot wire has voltage well past the GFCI that hasn't made it to the neutral. By your theory, that should trip the GFCI.
Voltage, with no path for current flow, will not trip a GFCI. The tank can be energized with no current flow just like the conductor wire. And as a Marine Electrician

Not that it matters, but I worked as a submarine electrician for 10 years with the final 3 1/2 teaching electrical theory. I'm now on my 18th year as an electrical engineer. You can believe me or not, that is up to you. My feelings won't be hurt either way.

That's not how a gfci works. My remarks about an electrical current swimming in a tank was sarcasm. Any imbalance between the hot and neutral triggers the GFCI. I understand what you are saying about the glass as an insulator which in fact makes the tank a capacitor at that point but with no current flow that means a piece of equipment isnt working.

 

[Brew12]

That's not how a gfci works. My remarks about an electrical current swimming in a tank was sarcasm. Any imbalance between the hot and neutral triggers the GFCI. I understand what you are saying about the glass as an insulator which in fact makes the tank a capacitor at that point but with no current flow that means a piece of equipment isnt working.

I know how a GFCI works. I need to do a better job explaining it. Let's take a pretend heater with a hot and a neutral and plug it into a GFCI. If you strip back a little insulation on the hot wire and wrap it in electrical tape, it won't trip the GFCI. Why? Because even if the voltage makes it to the inside edge of the electrical tape, it has no where for current to flow other than through the heater and to the neutral.
Now lets strip back a little insulation and put a cardboard tube over it and then wrap it in electrical tape. The heater will still work, but the GFCI will not trip because the voltage may reach the cardboard tube but there is no path for current to flow other than through the heater. You could fill that cardboard tube with salt water, and as long as the electrical tape created a good insulating barrier, it will not trip the GFCI.

Unless you have significant salt creep or some other path for current to flow to ground, the water in your tank will become energized but the glass will insulate it from ground. With no path for that current to flow to ground, all current flow will still only go to the neutral so the GFCI will not trip.

Does that make more sense?

 

[Cory]

This was a good thread!

Question: Whats best for the fish so they dont get shocked?

Anyone seen this?

Scientific research on Earthing / Grounding - Earthing Vitality

Scientific research on Earthing / Grounding

www.earthing-vitality.org

 

[Brew12]

This was a good thread!

Question: Whats best for the fish so they dont get shocked?

Anyone seen this?

Scientific research on Earthing / Grounding - Earthing Vitality

Scientific research on Earthing / Grounding

www.earthing-vitality.org

I don't believe marine fish can be shocked. The water they swim in is more conductive than they are so any current will flow around them, not through them. This is why you can only electrofish in fresh water.

 

[Cory]

I don't believe marine fish can be shocked. The water they swim in is more conductive than they are so any current will flow around them, not through them. This is why you can only electrofish in fresh water.

What do you think is healthier? Ground probe or not?

Question: if my tanks grounded durring a fault and im wearing rubber boots would i feel a shock? Would I feel a shock without the boots and on concrete?

And lastly, would i feel a shock without a probe wearing rubber boots?

 

[Cory]

The water they swim in is more conductive than they are so any current will flow around them, not through them.

But wouldnt electricity still follow all paths so the fish might still feel or sense it?

 

[Brew12]

But wouldnt electricity still follow all paths so the fish might still feel or sense it?

It does follow all paths but the difference in resistance is enough that, even with 20A flowing through your water, the fish would only get a few milliamps. There could be some negative impact to the fishes lateral line and other magnetic sensing organs and could contribute to HLLE but I'm not aware of any testing done on it.

 

[Brew12]

What do you think is healthier? Ground probe or not?

I run my tank with a ground probe and GFCI. That is the safest way to run an aquarium but I do it for more reasons than my personal safety. If I have a failing piece of equipment in my system it could be releasing copper and other toxins into my aquarium. The GFCI tripping immediately lets me know I have an issue and also reduces the rate toxins will be released.

Question: if my tanks grounded durring a fault and im wearing rubber boots would i feel a shock?

No. If you are wearing rubber boots and touching nothing else, you could grab a 120V hot wire in your bare hand and not be shocked.

Would I feel a shock without the boots and on concrete?

Most likely, yes.

And lastly, would i feel a shock without a probe wearing rubber boots?

Nope.

 

[Cory]

Most likely, yes.

Why most likely? Because we are a bigger electrical conductor than a wire?

So your saying fish dont get shocked. But small amounts of current can still pass through them. So they do get shocked, just in very small amounts.

However, your also saying that I wont get shocked if wearing rubber boots, with a ground probe (current flowing) or without(current standing). So why would the fish get shocked with a ground probe, but not me when wearing boots? Or is this just unknown to sciennce?

 

[bam123]

I took physics 101 and 102 at the university of Florida. From my experience, the ground probe plays a big role in making sure stray voltage does not dangerously overload the flex capacitor (this can have dire consequence in the time-space continuum).

 

[Brew12]

Why most likely? Because we are a bigger electrical conductor than a wire?

So your saying fish dont get shocked. But small amounts of current can still pass through them. So they do get shocked, just in very small amounts.

However, your also saying that I wont get shocked if wearing rubber boots, with a ground probe (current flowing) or without(current standing). So why would the fish get shocked with a ground probe, but not me when wearing boots? Or is this just unknown to sciennce?

woops... I think I misunderstood. I thought you were saying without a ground probe and not wearing boots.
If you have a ground probe connected to a properly grounded and bonded outlet, it would be almost impossible to get shocked under any situation.
I guess you could say fish could get shocked in very small amounts. However, it would be like saying you are getting shocked when you build up a static charge. There is no indication I know of that the fish react to current flowing through a tank. Interestingly, some studies do show they will align with the direction of current flow, likely because of the magnetic field it creates.

 

[Gablami]

Earlier in this thread, someone asked whether their titanium heater could serve as a grounding probe. Their heater did not have a third prong. But mine do (finnex titanium heaters). @Brew12, do I need to get a dedicated grounding probe, or would my titanium heaters suffice?

 

[Brew12]

Earlier in this thread, someone asked whether their titanium heater could serve as a grounding probe. Their heater did not have a third prong. But mine do (finnex titanium heaters). @Brew12, do I need to get a dedicated grounding probe, or would my titanium heaters suffice?

It would take a meter to verify for sure, but I highly suspect that it acts like a ground probe and there is no reason for a separate grounding probe.

 

[Connly33]

I know this thread is old, and honestly I only made an account for this reply as it's on the top Google results for aquarium grounding. All the complex replies in support of GFCI + grounding probe give good information, but as an electronic hobbyist that has to explain concepts to people all the time, it's not that hard.



If your tank does not have a path to ground, a GFCI won't trip if there is an electrical fault, UNTIL a nice path to ground, your arm, comes in contact with the water ONLY THEN there will be a fault current to detect for the GFCI. The fault current does not occur until there is a path to ground. With a ground probe there is a preemptive path to ground to detect the fault. GFCI measures current from line the neutral and trips if there is a difference, fault current can only go to neutral or ground, if it goes to neutral the GFCI does not detect an imbalance because there is not one, that is how current should be flowing, The GFCI only trips if it doesn't know where the current is going (to ground somewhere)



GFCI and no ground = only trips WHEN You get shocked, may save your life, but you still get shocked.



GFCI + ground in aquarium = GFCI trips if a fault occurs, as soon as it does, BEFORE you get shocked, given the fault current is sufficient.



Some of the replies from others that don't understand there can be voltage differential without current flow meaning a GFCI won't trip until there is a ground path to let current flow , hurts my brain.



Anyway, have a nice day lol

I was just looking to see if anyone actively grounds their aquarium and uses a GFCI as i just got a nasty shock from a busted heater in one of my freshwater tanks, and would not like to repeat that as half the heaters on the market are unreliable even if they are expensive name brands.

 

[Brew12]

I know this thread is old, and honestly I only made an account for this reply as it's on the top Google results for aquarium grounding. All the complex replies in support of GFCI + grounding probe give good information, but as an electronic hobbyist that has to explain concepts to people all the time, it's not that hard.



If your tank does not have a path to ground, a GFCI won't trip if there is an electrical fault, UNTIL a nice path to ground, your arm, comes in contact with the water ONLY THEN there will be a fault current to detect for the GFCI. The fault current does not occur until there is a path to ground. With a ground probe there is a preemptive path to ground to detect the fault. GFCI measures current from line the neutral and trips if there is a difference, fault current can only go to neutral or ground, if it goes to neutral the GFCI does not detect an imbalance because there is not one, that is how current should be flowing, The GFCI only trips if it doesn't know where the current is going (to ground somewhere)



GFCI and no ground = only trips WHEN You get shocked, may save your life, but you still get shocked.



GFCI + ground in aquarium = GFCI trips if a fault occurs, as soon as it does, BEFORE you get shocked, given the fault current is sufficient.



Some of the replies from others that don't understand there can be voltage differential without current flow meaning a GFCI won't trip until there is a ground path to let current flow , hurts my brain.



Anyway, have a nice day lol

I was just looking to see if anyone actively grounds their aquarium and uses a GFCI as i just got a nasty shock from a busted heater in one of my freshwater tanks, and would not like to repeat that as half the heaters on the market are unreliable even if they are expensive name brands.

Welcome to Reef2Reef!

Very well put. And yes, I don't use a ground probe anymore, but I have verified my titanium heaters work the same way. The ground wife is connected to the titanium housing.

 

[CMMorgan]

I know this thread is old, and honestly I only made an account for this reply as it's on the top Google results for aquarium grounding. All the complex replies in support of GFCI + grounding probe give good information, but as an electronic hobbyist that has to explain concepts to people all the time, it's not that hard.



If your tank does not have a path to ground, a GFCI won't trip if there is an electrical fault, UNTIL a nice path to ground, your arm, comes in contact with the water ONLY THEN there will be a fault current to detect for the GFCI. The fault current does not occur until there is a path to ground. With a ground probe there is a preemptive path to ground to detect the fault. GFCI measures current from line the neutral and trips if there is a difference, fault current can only go to neutral or ground, if it goes to neutral the GFCI does not detect an imbalance because there is not one, that is how current should be flowing, The GFCI only trips if it doesn't know where the current is going (to ground somewhere)



GFCI and no ground = only trips WHEN You get shocked, may save your life, but you still get shocked.



GFCI + ground in aquarium = GFCI trips if a fault occurs, as soon as it does, BEFORE you get shocked, given the fault current is sufficient.



Some of the replies from others that don't understand there can be voltage differential without current flow meaning a GFCI won't trip until there is a ground path to let current flow , hurts my brain.



Anyway, have a nice day lol

I was just looking to see if anyone actively grounds their aquarium and uses a GFCI as i just got a nasty shock from a busted heater in one of my freshwater tanks, and would not like to repeat that as half the heaters on the market are unreliable even if they are expensive name brands.

Thank you for this straight forward and easy to compute answer. I have been reading these threads for hours and I'm more confused then when I started. You make it easy... put in a grounding probe + a GFCI and I won't get zapped. Bonus --- rubber boots do not hurt.
drop mic - Elvis has left the building. Thank you, thank you very much.

 

[gcrawford]

Wow, just got an email for this thread update..... this was back when I was a reef tank hobbiest. Haven't had a tank in years and haven't been shocked either lol..... cheers reef community and happy holidays!