Grounding Probe - is it needed?

[jabberkaycee]

I just acquired a grounding probe but from reading several articles I'm confused as to if I even need it. I have a GFCI outlet but I'm unsure how a grounding probe works. My electrical equipment is housed in my sump - heater, skimmer and Mj1200 for my reactor. My recirculating pump in external, as well as my vortechs.

So what are the pros/cons? And exactly how do install it? It does not have a plug, just a small grounding loop at the end.

 

[MimicOcto8]

i've always been curious about ground probs. I've heard they are highly recommended but like you i'm not sure about them

 

[reefpeeper]

Basically you attach the loop onto the screw the holds the plate over your electrical socket. This inturn will attract any stray voltage that is in the tank to the probe and remove it. Electricity always follows the simplist ground and that would be it. I personally do not have one but maybe i should. Your gfi is only good for a sudden high voltage spike so that it will trip the circuit. The grounding probe is for stray voltage that may leak from electrical equipment that is in the tank. Some people in the hobby may say that they feel a slight shock when they put their hand in the tank. Well thats stray voltage. Overtime this can affect corals and fish. Hope this info helps.

 

[youngtimothy]

I'm not sure if they are needed but i've always thought better safe then sorry. I've had one in my tank for four years.

 

[VegasRick]

A properly installed GFCI is supposed to trip when there is a fault. Faults look for a path to ground, a ground probe provides this path. Heater and powerheads are known to fail.

There are a couple more reason to install them. Fluorescent lights induce voltage in metal reflectors and the metal frames. These frames and reflectors should be grounded along with the aquarium. This puts everything at the same potential. This is called equalized potential grounding and will keep you from getting shocked when reaching in the water and touching the lights by accident. Additionally powerheads that run off dc voltage wont necessarily trip the gfci and can give you a nasty shock.

It is also said that stray electrical voltage in the tank can stress fish and even cause HLLE. While there is no proof that it does, the fish have organs that are highly sensitive to electrical current so it is a reasonable assumption. Using a ground probe along with a gfci should eliminate these stray voltages

 

[LILBUDDHA]

A GCFI would cover this for you . I would say no . It's a gimmick . If you place one in your basically completing the circuit .

This is why . You are providing a current path that might not already exist. Any fish between the source and the grounding probe will experience a current flowing through their bodies... not good! The fish is swimming around in the water . It is not attached to anything . Not like you can insulate it from within .

 

[MimicOcto8]

thats awesome three good pieces of info there. 2 people saying yes and explaining what it does and a 3rd saying its worthless. I love this place

 

[jabberkaycee]

haha - now you can see why I'm so confused! I appreciate all the feedback so far - more is welcome.

 

[LILBUDDHA]

Okay . I'll confuse you more :wink:

Here is a article on it . Hope it clears the air . I gave the short version LOL


Conventional wisdom found in magazine articles and in the bowers of world wide web chat
rooms indicated that “voltage†in aquaria is one of the factors that can cause Hole in the Head and Lateral Line Erosion. We read quotes like, “Stray voltage is something that exists in every tank. Stray voltage can be eliminated with a simple ground probe available at most pet shops in the twenty dollar range. Elimination of stray voltage is a simple step in reducing the stress on your fish. Every marine tank should be grounded for your protection and that of your fish.â€

Is it true? Well not exactly, and as I will discuss below, the addition of a ground probe may even make matters worse!

Clearly electrical items submerged within your aquarium (power heads, heaters, etc.) can provide a direct interface between the prime power source (120 volts alternating (60 Hz) current (VAC) in the United States and 220 VAC, 50 Hz in most of the rest of the world) and the water, but some claim that the stray voltages can be indirectly induced by the lighting systems. This is possible because the skin depth of salt water (a conductor) at 60 Hz is not zero. “Skin depth†is the distance that electromagnetic energy can penetrate a conductor. Salt water is a conductor, but not a perfect conductor, so there is penetration by 60 Hz emissions. These induced voltages are small in magnitude. On the other hand, shorted pumps can develop large currents through the water, but typically between the “short†and some “ground†like your ground probe. This means that the inclusion of a ground probe could make things worse. If a pump were shorting within itself, the currents flowing through the water would remain local to the pump and should not be a problem. You would have to have two shorting pumps, or a pump and a ground probe, or some other current path to get electrical current to flow through your tank.

Direct shorts would have other ramifications. Copper or iron could be introduced into the aquarium water as plating occurred. Other compounds would plate out as well since salt water contains many ions in suspension. Electrolysis would occur, heating the water while it liberated oxygen and hydrogen. There is of course a shock hazard.

Most people do not understand the problem however. Lots of web space has been devoted to the measurement of voltage in aquariums... most of which is of no value. Voltage is not the problem, current is. Voltages can exist without there being any current. For example, birds sitting on a power line may be in direct contact with 10,000 volts, but they are not electrocuted. Why? Because no current is flowing through their bodies. Voltage is the “potential†or force that drives electrons through a conductor. The actual flow of electrons is the “currentâ€. It is current that kills. Were one of the birds sitting on the power line to simultaneously touch one of the other wires on the transmission pole, a current path would be created (through the bird) and it would be electrocuted (and probably incinerated as well). So what are you doing when you add a grounding probe to your aquarium? You are providing a current path that might not already exist. Any fish between the source and the grounding probe will experience a current flowing through their bodies... not good!

Taking a volt meter and measuring a voltage in your aquarium relative to some arbitrary ground point does not indicate that there is a current flowing through the salt water (conductive medium) in your aquarium! It just means that the aquarium water is at a different potential than the ground reference point that you chose.

Measuring a voltage between submerged points in your aquarium may be misleading if not done correctly. The use of metallic probes can create a “battery effect†if dissimilar metals are involved (think your volt meter probes are the same metal? What if they are chrome plated (most are) and what if you’ve worn the chrome off one to expose brass or copper beneath?).

Also, some currents in salt water are perfectly natural as described below.

You can measure electrical currents everywhere-- the fact that salt water ions flow, actually generates an electrical current. Its unavoidable. The open ocean has lots of electrical currents flowing. Some of these are caused by currents flowing through the Earth while others are actually perturbations to local fields caused by the motion of objects (fish, turtles, etc.) in the water. When I was tracking the Florida Manatee (Trichechus manatus) in the Banana and Indian Rivers around the Kennedy Space center, we actually considered sensing the extremely low frequency (ELF) emissions generated by the manatee’s tails as they accelerated the brackish or salt water ions in the presence of the Earth magnetic field during vigorous swimming (alas, manatees are not very energetic most of the time and other means were chosen (Sirenian Tracking Project)). For example, the ampullae of Lorenzini in a shark’s nose detect minute current flow disturbances in the water as an aid in locating prey.

I don't use any power heads and all of my pumps are totally external and physically isolated (motor and pump head are separate). With the exception of an emergency heater in the sump, no electrical appliances come in contact with the water.

There are all sorts of anecdotes about how much better the fish in a given tank will act and look after adding one of these “grounding probesâ€. My belief is that if there are any stray currents in the tank coming from an electrical appliance, the solution is not to try to draw the current away with a grounding probe (symptom), rather, the appliance must be damaged and should be replaced (cure).

Fish don’t like electrical current to flow through their bodies. When higher electrical current levels flow through the water, fish will orient their bodies to minimize the potential (voltage) across their bodies, thereby minimizing the electrical current flowing through their bodies. At very low levels, the fish may only act strangely or seek areas of the aquarium where electrical current is not flowing. It is doubtful that continuous current flow through a fish’s body is beneficial, and may in fact be the source of anecdotal reports of Hole in the Head disease and Lateral Line Erosion. If your tank is at a different potential from the “ground†in your house, no electrical current may exist in your tank based on this static voltage. However as soon as you ground your tank by inserting a “grounding probeâ€, you will be guaranteed to have electrical current flowing even if the voltage drops.

In conclusion, the addition of a “grounding probe†will guarantee an electrical current flow in your aquarium and may induce erratic behavior or disease in your fish. If you have defective aquarium appliances that are creating a current path in your aquarium by using the salt water as a conductive medium, then the solution is to repair the appliances or replace them... not diert a portion of the current into a “grounding probeâ€.

HTH

 

[VegasRick]

The article lilbuddha posted is accurate but not quite complete. And I have argued both sides of this so many times its not even funny.
You might note the author uses no power heads and only one emergency heater. Not too many actually do it this way. And he doesn't even mention GFCI
Electricity doesn't take the shortest path to ground, it takes every path to ground with the majority of current taking the path of least resistance. So if you have a shorted pump, you have about a trillion different paths between the 2 points.
The key here is use of a GFCI with a ground probe. This senses the short and interrupts the circuit. As the article stated without a ground probe you actually have to have 2 pumps shorted to have the path to ground, thats also depends on the type of failure in the equipment. Otherwise the path to ground is you, next time you stick you hand in the tank.. When you have a gfci that trips you know there is a problem and can eliminate it before it becomes a hazzard.
As I mentioned above gfci won't necessarily trip with the dc powered pumps. I have found this out from personal experience. And with a ground probe you wont even notice the short. So its kinda a catch 22 on this.
In the end my personal safety always wins out. I use a ground probes and GFCI

 

[MAXreefer]

Interesting thread.
I read some horror stories GFCI outlets tripping for no reason causing a major disaster in the tank if it happens when the owners are not at home.
What causes them to fail actually?

 

[milkman]

My experience is the probes work. I had a brand new 75 gal sump feeding eight 20 gal breeders. I put a new Mag 12 pump submerged in the sump. I immediately would feel a very mild shock in any of the eight tanks. If I unplugged the Mag, it stopped. I added a grounding probe in the sump and everything was fine.

On my reef setup, I don't have a probe and have no issues, but I have all external pumps other than the skimmer feed pump.

 

[LILBUDDHA]

I use to use them . A buddy who is a is a electrician installed a GFCI circuit for my tank . Actually he installed a few in the home. One has failed or had to be replaced . Thank the Universe it was just the XMAS outside lights . A voltmeter tells the story imho. Trace it to it's source and remove the cuplrit . At least that's my solution . I have seen poorly manu pumps, powerheads and heater's to usually be the culprits of tank disasters. Koriallas ? and some chinese pumps are very capable of this . In my area these pumps are widely used . Some get bit and some don't .
Anywho it's good to see a nice chat without the other stuff going on.

 

[firefightered]

I just had a bad experiance with 4 MJ-1200s and a stealth heater. I noticed my fish where acting kinda funny and my female clown had a black spot under her bottum lip. When I got close to my tank the hair on my arm stood up due to static elec. I unplugged every thing and got a seperate bucket of water. I started testing everything in my tank that was elec. I found (using fresh water from my tap) That all 4 power heads and a sealth heater was leaking elec. The stealth had a recall on it so that was taken care of with the LFS. I called cutomer service on the MJs and they are going to send me 4 new MJs. I had a total of 36 volts running through my tank and refugeum!!!!!! I use a GFCI and it never tripped plus everything goes through a surge protector as well. I don't have a grounging probe yet and have been doing a lot of research on this forum about them. There is a lot of opinions on these things with alot of diff. answers. If there is a good electrician on here Now would be the time to chime in and give the expert opinion.................. By the way, 2 days after I disconnected the voltage leaks, the black spot was gone......

 

[jabberkaycee]

ok - so stupid question. How exactly do I install the grounding probe? Do I take the cover off the GFCI and, then I assume, there is a grounding screw????

 

[jabberkaycee]

ok - so stupid question. How exactly do I install the grounding probe? Do I take the cover off the GFCI and, then I assume, there is a grounding screw????

Anyone? It doesn't have a plug, just the round groud connection....

 

[ericbe]

You have a picture jabberkaycee? On my surge protector you can wire a ground into the recepticle that feeds into the buildings ground. On a theoretical addition, wouldn't when using a ground plug and upon a fish entering the path of a ground directed voltage, the electricity just flow around the less salty fish? Also how can you wire a ground probe up to a buzzer so you know when a potential copper leak is entering the tank and when an electrical applience needs to be replaced without receiving a shock-- when you happen to be barefooted.

 

[ericbe]

Also when a ground probe is connected, does Wifi and radio signals get picked up and carried down the ground and if so what you a piezoelectric speaker in the middle sound like at that range? Or can you block out certain frequencies, if this is the case with salt water.

 

[Waters]

I use them strictly for the fact that I have been zapped without using them.