Ground probe - AND GFI???

w16227 · 02/05/2010, 02:40 PM

I usually use coral-life gloves when my hands are in the tank.

Yesterday, I was removing my veggie clip and my "bare" finger went in the tank (usually does not happen) and I fely a stinging sensation. I do have a small cut healing in the finger - so I wrote this off as the salt content.

Now - not so sure.

I have GFI on all of my power outlets - and I though that this would not necessitate the need for a ground probe.

The worry of course is stray voltage - but shouldn't this trip the GFI? Shoudl I be running a ground probe as well?

I have not noticed anything strange with my fish - but some of my corals have been acting weird lately. Both my water tests and my LFS say everything is in the good range (0 am, almost undetectable nitrate, 0 phos, 400+ calcium, 8-10 dKh).

Coral issues - superman monti bleaching in patchy locations, lost a minti cap that has been in the tank for over 6 months and a chalice that was growing well from a smaller frag went through what I would call STN (dissolved over a week).

These corals have been with me for a while - and survived some real rookie mistakes. Others- like an 8 month old red monti cap and a newer acro that has only been in the tank for 2 weeks- look perfect.

Obviously - the coral issues can be caused by many other things - but lets focus on the stray voltage for a moment.

1. Do you need a ground probe with GFI outlets?
2. Is is possible for stray voltage to irritate individual corals - or would I see more of a whole tank affect?
3. Any risk with running a ground probe with a GFI outlet?

Looking for things to eliminate as far as the coral failings go. This is one of the areas where I am at a bit of a loss,,,,, (the ground probe - not things like reef chemistry or husbandry/predators).

THANKS

CJO · 02/05/2010, 03:59 PM

You do need a ground probe, even with a GFI. It should not trip the GFI unless you have a lot of current flowing in your tank. No idea on whether it would affect everything or just more sensitive things. You may want to try unplugging your things one at a time until you figure out where the extra current is coming from.

CJ

Shane Hoffman · 02/05/2010, 04:56 PM

The first thing I would do is figure out exactly how much stray voltage you have. You may have a lot coming from one piece of equipment or you may have 14 volts coming from 14 pieces of equipment. I have seen it both ways. If you have one thing causing a drastic spike I would replace it. I cant offer a definitive opinion on the ground probe. I have read way to many differing opinions on their usage. ome say they cause more harm than good. Their theory is that when installing a ground probe you are completing a circuit. Then when something wonders in the path of said circuit it feels the shock of the total stray voltage in the tank. Thes same people say it is better to not have one and then worst case scenario is the livestock only feel minimum amounts occasionally. My problem with that theory is that if an animal feels a shock that means it is completing the circuit, now is it feeling all of the stray voltage or just a bit....IDK. What I do know is that energy takes the path of least resistance so wether it is a fish or a ground probe it could be either or at any given time. I truly wish someone would do some experiment and nail this one down. I am guessing its hard to hook up electrical sensitivity devices to fish to find out...anyhow all of that probably didnt help alot....heres is what I do, and I am having great success with all of my coral and fish at the moment. I have 13volts of stray voltage. These 13 volts come from 17 different pieces of equipment in my tank. I kid you not, EVERY piece of equipment that touches my water leaks a minimum of .3 volts up to 1.1volts. I have chosen not to use a ground probe and still have success. I am of the group of people that say if it aint broke dont fix it. If I ever have problems I cant attribute to something I will try the ground plug. Until then it will be status quo.......

w16227 · 02/09/2010, 12:22 PM

Quote:

Originally Posted by Shane Hoffman

The first thing I would do is figure out exactly how much stray voltage you have. You may have a lot coming from one piece of equipment or you may have 14 volts coming from 14 pieces of equipment. I have seen it both ways. If you have one thing causing a drastic spike I would replace it. I cant offer a definitive opinion on the ground probe. I have read way to many differing opinions on their usage. ome say they cause more harm than good. Their theory is that when installing a ground probe you are completing a circuit. Then when something wonders in the path of said circuit it feels the shock of the total stray voltage in the tank. Thes same people say it is better to not have one and then worst case scenario is the livestock only feel minimum amounts occasionally. My problem with that theory is that if an animal feels a shock that means it is completing the circuit, now is it feeling all of the stray voltage or just a bit....IDK. What I do know is that energy takes the path of least resistance so wether it is a fish or a ground probe it could be either or at any given time. I truly wish someone would do some experiment and nail this one down. I am guessing its hard to hook up electrical sensitivity devices to fish to find out...anyhow all of that probably didnt help alot....heres is what I do, and I am having great success with all of my coral and fish at the moment. I have 13volts of stray voltage. These 13 volts come from 17 different pieces of equipment in my tank. I kid you not, EVERY piece of equipment that touches my water leaks a minimum of .3 volts up to 1.1volts. I have chosen not to use a ground probe and still have success. I am of the group of people that say if it aint broke dont fix it. If I ever have problems I cant attribute to something I will try the ground plug. Until then it will be status quo.......

Same confusion as you (probe or no probe)- though some searching may give some clues.

http://angel-strike.com/aquarium/GroundingProbes.html

one of the better articles -

Seems that some of the confusion is the result of the concept of leaked vs induced voltage. Leaked being voltage from a component directly (faulty wiring or housing) and induced from water motion or te act of placing an AC power source in the water.

Leaked voltage = faulty equipment and a ground probe will most likely trip a GFI - but induced voltage may not.

A couple of tidbits that I found - I am not posting the direct link as it is to another reef message board- but the poster (Paul B) claims to be an electrician and his statements seem pretty reasonable to me.

"The ground probe is there to protect you, not the fish."

Makes sense -- if there is already a grounded leak (not induced) - where the fish would see the voltage, the GFI should trip. For induced -- there is not a ground path and the fish would not be affected (same reason that birds can sit on high voltage wires).

He does recommend the ground probe - as there is a chance of you making a circuit with your body - and NOT tripping the GFI.

In any case - dummy me put another finger in and did not feel a shock so I did not take the time to probe the tank. Did not realize (more reading) that you may not feel anything without a cut/hangnail unless there is an extreme amount of stray volts.

In any case - going with the electricians recommendation and adding a probe---- after I use the meter and see if any components may have exposed wiring.

sowellj · 02/09/2010, 03:54 PM

I have stray voltage in my tank and wrestled with this a bit. I decided to leave it be. Unless the voltage has a path, current will not flow. The only time I notice it is if I put my hand in my tank while barefoot. I think it boils down to your safety or the inhabitants ... If you do have a grounding probe and GFI, the current will flow to ground and the inhabitants may feel it. This is the safer route for people. Conversely, if the tank is not grounded it just sits at a potential and the inhabitants are not aware of it as current is not flowing. Really just depends on how much voltage and how easy it is to isolate/fix.

wab · 02/09/2010, 04:31 PM

Imo the fish wont feel the path to ground, the same way as stated earlier birds squirrel etc can land and run on live uninsulated lines. There is no difference in potential for current to flow. If you have no ground rod then the potential (electricity in your tank grows). If you kneel on the floor, have no shoes on, touch tank and any ground and wamo discharge. I work for the phone co and if we test the cable and have a power condition we first ground the cable to remove the induced voltage and if after its still has potential we call the power co because they (or us)have faulty eq. I have both gfi and ground probe. Hope it helps

bertoni · 02/09/2010, 06:14 PM

Quote:

http://angel-strike.com/aquarium/GroundingProbes.html

I don't think that article is very well thought out, personally. If there's current in the tank, any substantial amount, almost certainly some piece of equipment is leaking it, and a GFCI and a ground probe can improve personal safety a lot and help diagnose the problem. I keep equipment on multiple GFCIs, so that one bad piece of equipment doesn't shut down a tank, but I always use them along with a ground probe. That approach can save your life or keep your house from burning down.

02/05/2010, 02:40 PM	#1
w16227 Premium Member Join Date: Feb 2005 Location: chicago Burbs Posts: 479	Ground probe - AND GFI??? I usually use coral-life gloves when my hands are in the tank. Yesterday, I was removing my veggie clip and my "bare" finger went in the tank (usually does not happen) and I fely a stinging sensation. I do have a small cut healing in the finger - so I wrote this off as the salt content. Now - not so sure. I have GFI on all of my power outlets - and I though that this would not necessitate the need for a ground probe. The worry of course is stray voltage - but shouldn't this trip the GFI? Shoudl I be running a ground probe as well? I have not noticed anything strange with my fish - but some of my corals have been acting weird lately. Both my water tests and my LFS say everything is in the good range (0 am, almost undetectable nitrate, 0 phos, 400+ calcium, 8-10 dKh). Coral issues - superman monti bleaching in patchy locations, lost a minti cap that has been in the tank for over 6 months and a chalice that was growing well from a smaller frag went through what I would call STN (dissolved over a week). These corals have been with me for a while - and survived some real rookie mistakes. Others- like an 8 month old red monti cap and a newer acro that has only been in the tank for 2 weeks- look perfect. Obviously - the coral issues can be caused by many other things - but lets focus on the stray voltage for a moment. 1. Do you need a ground probe with GFI outlets? 2. Is is possible for stray voltage to irritate individual corals - or would I see more of a whole tank affect? 3. Any risk with running a ground probe with a GFI outlet? Looking for things to eliminate as far as the coral failings go. This is one of the areas where I am at a bit of a loss,,,,, (the ground probe - not things like reef chemistry or husbandry/predators). THANKS __________________ call me "w" - easier to remember Current Tank Info: 125g All Glass rr, 50g sump/fuge, RKE, T5 Retrofit Lights, Deltec Turbo Skimmer, PM Kalk Reactor

02/05/2010, 04:56 PM	#3
Shane Hoffman Registered Member Join Date: Mar 2009 Location: 45 mins from Chicago Posts: 2,009	The first thing I would do is figure out exactly how much stray voltage you have. You may have a lot coming from one piece of equipment or you may have 14 volts coming from 14 pieces of equipment. I have seen it both ways. If you have one thing causing a drastic spike I would replace it. I cant offer a definitive opinion on the ground probe. I have read way to many differing opinions on their usage. ome say they cause more harm than good. Their theory is that when installing a ground probe you are completing a circuit. Then when something wonders in the path of said circuit it feels the shock of the total stray voltage in the tank. Thes same people say it is better to not have one and then worst case scenario is the livestock only feel minimum amounts occasionally. My problem with that theory is that if an animal feels a shock that means it is completing the circuit, now is it feeling all of the stray voltage or just a bit....IDK. What I do know is that energy takes the path of least resistance so wether it is a fish or a ground probe it could be either or at any given time. I truly wish someone would do some experiment and nail this one down. I am guessing its hard to hook up electrical sensitivity devices to fish to find out...anyhow all of that probably didnt help alot....heres is what I do, and I am having great success with all of my coral and fish at the moment. I have 13volts of stray voltage. These 13 volts come from 17 different pieces of equipment in my tank. I kid you not, EVERY piece of equipment that touches my water leaks a minimum of .3 volts up to 1.1volts. I have chosen not to use a ground probe and still have success. I am of the group of people that say if it aint broke dont fix it. If I ever have problems I cant attribute to something I will try the ground plug. Until then it will be status quo....... __________________ A wise man once said "Never play leap frog with a unicorn" Current Tank Info: 150 gallon glass with 20 gallon sump, 175lbs of coraline covered live rock, EuroReef skimmer rated for 250gal, 25watt Aqua UV sterilizer, Fluval FX5, Hamilton 3x250watt MH, 160 watt Blue actinic....Mixed reef

02/09/2010, 04:31 PM	#6
wab Registered Member Join Date: Apr 2008 Location: nj Posts: 512	Imo the fish wont feel the path to ground, the same way as stated earlier birds squirrel etc can land and run on live uninsulated lines. There is no difference in potential for current to flow. If you have no ground rod then the potential (electricity in your tank grows). If you kneel on the floor, have no shoes on, touch tank and any ground and wamo discharge. I work for the phone co and if we test the cable and have a power condition we first ground the cable to remove the induced voltage and if after its still has potential we call the power co because they (or us)have faulty eq. I have both gfi and ground probe. Hope it helps __________________ 1 year plus and still I DON'T KNOW!!!! LOL Current Tank Info: 45 high 30 breeder sump/refuge diy

02/05/2010, 03:59 PM	#2
CJO Registered Member Join Date: Dec 2009 Location: Charlotte, NC Posts: 578	You do need a ground probe, even with a GFI. It should not trip the GFI unless you have a lot of current flowing in your tank. No idea on whether it would affect everything or just more sensitive things. You may want to try unplugging your things one at a time until you figure out where the extra current is coming from. CJ

02/09/2010, 03:54 PM	#5
sowellj Registered Member Join Date: Jul 2008 Location: greenwood, sc Posts: 712	I have stray voltage in my tank and wrestled with this a bit. I decided to leave it be. Unless the voltage has a path, current will not flow. The only time I notice it is if I put my hand in my tank while barefoot. I think it boils down to your safety or the inhabitants ... If you do have a grounding probe and GFI, the current will flow to ground and the inhabitants may feel it. This is the safer route for people. Conversely, if the tank is not grounded it just sits at a potential and the inhabitants are not aware of it as current is not flowing. Really just depends on how much voltage and how easy it is to isolate/fix.