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alton
Wed, 26th Jan 2011, 08:00 AM
I post this every one or two years here on MAAST. It is a very old post as you can tell from the post from Richard at the end. Once again please do not "DO WHAT I DO"!

Stray Voltage
Before I get started “I DO NOT RECOMMEND” to anyone to do the things I have done for my test!
With that I am covering Stray Voltage in and around your aquarium. This does not cover stray current in your tank! If you are getting a tingle when you touch your water, find out what is causing it and remove it, do not go out a buy a grounding probe thinking this will fix the problem. I recommend only using power heads and other equipment that is grounded (Has three prongs). I have never had problems with stray voltage or so I thought till last week when I checked all three of my aquariums. The reason I say that is because I am barefooted on a tile floor with my hands and arms submerged all the time with no tingle, so how could I have voltage? I have checked in the past with a meter with no voltage showing. Just recently I had made changes to my 200 gallon aquarium, but I figured no tingle no voltage right? The following is what I came up with all electrical equipment and lighting for the following tanks:

Tank #1 - 200 gallon, wet dry filter system, Mag. pump for the skimmer, Pan World 100PXX for the return. On lighting, 2 – 250 watt MH, 4 – 54w T5HO, 1 – 160 watt VHO.
Stray voltage – 14.5 volts and yes no tingle, even when I was barefooted and wet floor. Turn off the metal halides and it drops to 8.5 volts, turn off the rest of the lighting and it drops below 2 volts. For a clarification my hood is brand new, with no salt crepe or moisture and the lamps are a minimum of 8” above the water.

Tank #2 – 155 gallon, wet dry filter system, Mag. pump for the skimmer, Pan World 50PXX for the return. On lighting, 2 – 250 watt MH mounted in a 5’ Orbit light
Stray voltage – less than .5 volts with everything running. Clarification light is metal and grounded and the tank has glass tops.

Tank #3 – 29 gallon with an eclipse three filter system. The lighting consists of a 96 watt Quad PC with a 2 ½” fan from Radio Shack for cooling.
Stray voltage – 9 volts and once again no tingle. I grounded the reflector and the voltage only dropped a volt. Turn off light and voltage is below .5 volts. For clarification once again no moisture everything is dry, lamps is mounted only 3” above the water.

Solution: Installed a grounding probe into sump of tank #1 and one into the tank of #3 and voltage dropped below one volt in each.

GROUNDING PROBE – Good or Bad?
Let’s cover the bad things first:
If your service ground is bad outside it will use your tank as a ground and you will get more than a tingle. Example I got a call from a friend and he told me he was getting shocked when he put his hand in his tank. So I took a voltage reading and only 5 volts to the meter but to the hand it wasn’t very pleasing. Took out the grounding probe and voltage and shock was gone. I went to the service and added another ground rod and it took care of the problem. He left the probe out of his tank.
If you have a lightning strike near your home you have a chance of the voltage finding your way into your tank.
If you are going to install a grounding probe lets cover the basic setup for a safe operation:
Check your service for a ground rod some homes in SA do not have one. Go to where your meter is and look below your service panel or disconnect for#6 or larger wire leading into the ground. The ground rod should be buried below. If you cannot find one call an electrician to install one. If you are in soil keep the area moist especially now in dry times, this the main reason we lose our grounding. If you are in rock same thing make sure and keep the soil wet because you have less soil and solid rock does not make a good grounding substance. If you are building a new home add an additional grounding source to your ground rod by attaching a grounding conductor of #4 copper wire to a minimum of 20’ of rebar in your slab and attach it in two places and then attach it to your service panel grounding bar. To check and make sure you do not any voltage on your grounding conductors take your meter and place the probes across the grounding (green) and grounded (White) slots of several receptacles through out your house, the voltage should be 0. And then attach the probes across the ungrounded (black or red) slot and the grounding slot, and then the ungrounded slot and grounded slot. Determining which slot is which is easy. Looking at the receptacle the “U” shaped one is the grounding. The largest of the straight slots is normally the grounded with the smaller of the two being the hot or ungrounded. If you have voltage from the grounded and grounding slots (1 to 50 volts) you have poor grounding, call an electrician. If you have 120 volts then your grounded and ungrounded conductors could be reversed. (Call an electrician) Remember black or red goes on gold and white goes on silver, and of course the green or bare wire goes on the green terminal.
If everything is perfect than install your grounding probe, but don’t forget about it every once in a while you will need to check for voltage. It’s just like checking your GFCI receptacles to make sure they are working properly. Just because you have one doesn’t mean you’re safe. That is why there is a test button.

Some issues with Stray voltage and fish:
The reason why I started this article was my Chevron Tang started getting HLLE and I couldn’t figure out why?

(From Richard at CB pets)
We know from experience that certain fish may do poorly in tanks which have stray voltage. One example is an imperator angel we had in qt that was doing really well. Moved him out for sale and all he did was hide in the corner and would not eat. Moved him back to qt and he acted fine. Moved him back out and he quit eating. Hmmmm...so I checked for stray voltage on the tank and it was 16 volts. Added a grounding probe and he immediately started swimming around normally and ate when I fed him. So I took out the grounding probe and he immediately swam to the same corner and would not move. Put it back in and he was back to acting normal.
I guess some fish are more sensitive to it than others but since they sense electrical voltage it is probably a stressor to some degree for all fish.
Some say that stray voltage could be the cause (or one of them) for HLLE.
This isn't proven but but makes some sense to me.

Europhyllia
Wed, 26th Jan 2011, 08:21 AM
Great info Alton. Thanks for sharing it :)

allan
Wed, 26th Jan 2011, 09:25 AM
I recently, and my daughter Milly by biological default, suffered this method of troubleshooting stray voltage.

In our case it was a pump that seized up. We were unable to reach into the tank unless wearing shoes or in Milly's case when she stood on the step ladder to reach into the tank at my request. Of course when I grabbed her arm (I was barefoot on tile) she quickly let out a yelp and promptly dropped a prized frag.

Really, I don't know why I keep her around. :)

ShAgMaN
Wed, 26th Jan 2011, 10:00 AM
Great info, thanks Alton.

Karin, I got a PM from Alton with his number and will call him when I get home this evening. We'll figure it out, thanks.

BTW your PM inbox is full - which is why I'm posting this here.

aquasport24
Wed, 26th Jan 2011, 12:16 PM
Great info, btw a small cut on your finger will feel the same tingle feeling, so make sure to check with a good finger.

ErikH
Wed, 26th Jan 2011, 12:59 PM
Great info, btw a small cut on your finger will feel the same tingle feeling, so make sure to check with a good finger.


Ha, true! I always have to check with another finger too! One time my hands were so cut up I had to have my wife check. She was NOT happy. :)

ShAgMaN
Wed, 26th Jan 2011, 07:09 PM
Man, thanks for the help Alton! Turns out it was a K4 which spiked voltage up to 78 volts:what_smile: The K4 is out, and I'm down to 13 volts with no shock.

So I'm wondering if a grounding probe is really a good thing? Wouldn't this complete the circuit and possibly make things worse. I'm guessing the reason my fish were fine is cause my tank wasn't grounded. But the grounding probe would probably give you protection against electrocution. Hmmmmm.......

Oh, and anyone have a K4 (or equivalent) for sale? :)

Europhyllia
Wed, 26th Jan 2011, 07:12 PM
Alton is the man. :)

Wow Terry, I am so glad you didn't get seriously hurt!

(just for my own info: was the K4 plugged into a GFCI?)

I always heard to only use a grounding probe if everything is in GFCI so that it trips and we're safe. If it's not in GFCI outlets then the grounding probe could actually make things worse for us.

Your answer will be my answer in regards to this being a possibility or not.

StevenSeas
Wed, 26th Jan 2011, 07:17 PM
Man, thanks for the help Alton! Turns out it was a K4 which spiked voltage up to 78 volts:what_smile: The K4 is out, and I'm down to 13 volts with no shock.

So I'm wondering if a grounding probe is really a good thing? Wouldn't this complete the circuit and possibly make things worse. I'm guessing the reason my fish were fine is cause my tank wasn't grounded. But the grounding probe would probably give you protection against electrocution. Hmmmmm.......

Oh, and anyone have a K4 (or equivalent) for sale? :)

told ya it wasnt the light :angel: Luckily though you were able to find the cause and everything is all good. and a K4 is a lot easier to replace than an ATI fixture

ShAgMaN
Wed, 26th Jan 2011, 07:44 PM
told ya it wasnt the light :angel: Luckily though you were able to find the cause and everything is all good. and a K4 is a lot easier to replace than an ATI fixture

Heeh, didn't you say it was prolly the heater? Anyway, ya I was pretty sure it was the fixture, especially after taking the heater out and still having the problem...wrong! The fixture just provided a good ground. I never even felt a tingle on hard wood floors barefoot w/ 78 volts.

ShAgMaN
Wed, 26th Jan 2011, 07:48 PM
Alton is the man. :)

Wow Terry, I am so glad you didn't get seriously hurt!

(just for my own info: was the K4 plugged into a GFCI?)

I always heard to only use a grounding probe if everything is in GFCI so that it trips and we're safe. If it's not in GFCI outlets then the grounding probe could actually make things worse for us.

Your answer will be my answer in regards to this being a possibility or not.

Initially the K4 was not plugged into a GFCI, however it didn't matter, cause I plugged into one later and it never tripped.

Europhyllia
Wed, 26th Jan 2011, 07:51 PM
Oh man. You are totally bursting my bubble.

So is there a way to constantly monitor voltage or current in an aquarium?

What is the amp setting on the RKL for?

StevenSeas
Wed, 26th Jan 2011, 10:35 PM
Heeh, didn't you say it was prolly the heater? Anyway, ya I was pretty sure it was the fixture, especially after taking the heater out and still having the problem...wrong! The fixture just provided a good ground. I never even felt a tingle on hard wood floors barefoot w/ 78 volts.

OK you got me I did say it was probably the heater... so we were both kinda right in we knew what WASNT causing it but both lost on what it was lol. But that is strange you never felt it before with that high of voltage, guess it then depends on current too... hmm

alton
Thu, 27th Jan 2011, 08:23 AM
Remember voltage doesn't shock you current does. You can have a little as 5 volts and still get shocked. Terry in your case if you would of had a grounding probe it would of tripped your GFCI (for the wrong reason but either way it would of tripped just like it did when I had you use your meter the incorrect way).
Grounding probes are good for stray voltage not current leaking into your tank.
Karin on what is the best way to find out if you have current in your tank? I am going to be working on that to come up with a simple solution besides getting shocked. And as we found out GFCI's are not 100% fool proof!
Also older GFCI receptacles have to be tested because they fail on, the newer ones are suppose to fail off?
The best case scenero would be to have three GFCI receptacles
One for Lights
One for Non-essential loads like heaters and power heads
One for your main return/circulation pump
That way one would not trip the other. Nothing worse that going on vacation and a bad heater/power head trips the GFCI and your return pump doesn't work

Europhyllia
Thu, 27th Jan 2011, 08:27 AM
so voltage is bad for the fish, current is bad for people.
grounding probes are for the fish's benefit then? Yes? GFCI (if they work) are for the people

alton
Thu, 27th Jan 2011, 08:31 AM
I would say current is bad for fish too, it is just we find out that we have current in out tank the hard way and quickly. Where as voltage in the tank can go undetected by us.

allan
Thu, 27th Jan 2011, 09:04 AM
Actually, you can't have voltage without current or current without voltage. I've always looked at voltage as the vector in which current travels however that isn't a very good or accurate way to describe the relationship.

But voltage, current, and resistance is always there in some proportion relative to each other. I will agree that it is the current that you feel, and there will be times that the current is so low you won't feel it.

StevenSeas
Thu, 27th Jan 2011, 09:05 AM
I am not sure I fully comprehend. You cant have voltage without current or current without voltage right? So then how can you have stray voltage but not stray current? In order to have one you must have the other right?

StevenSeas
Thu, 27th Jan 2011, 09:06 AM
dang you beat me Allan

allan
Thu, 27th Jan 2011, 09:11 AM
nah, we were typing at the same time :)

But you are right, if one is present, so is the other. Perhaps not measurable by touch, but it's there.

Europhyllia
Thu, 27th Jan 2011, 09:28 AM
current only happens when there's something to complete the circle/ground it. No?

Europhyllia
Thu, 27th Jan 2011, 09:29 AM
like a lizard walking on the electric tape fence around the pasture just fine but as soon as it touches the wire fence below: fried

StevenSeas
Thu, 27th Jan 2011, 09:35 AM
no becuase there is current and voltage going through the electric fence. If you are making only 2 point of contact (or 4 in the lizards case) and all are with the electric fence then the electricity (both current and voltage are going through you, but not so much because its a longer path so more resistance) but once you ground yourself on something like another wire then essentially what you have done is completed a parallel circuit instead of a series circuit. So the electricity has now found a new path of least resistance.

The reason you feel electricity is from high current, but you have to have voltage to have the current or you have no electricity. The higher the current the more you are going to feel it. high current is what kills something not the voltage.

allan
Thu, 27th Jan 2011, 09:38 AM
lol, yes you are correct.

We always call that potential. If the potential is there all you need is someone to complete the circuit. Once that happens you are instantaneously aware of the problem as it attempts to travel through your arm at something less than 186,000 miles a second. :) When I work with voltage in the house I typically don't turn off my circuit... I just work with one wire at a time and remain ungrounded (wearing shoes and not touching anything that may be grounded). Doesn't always work and occasionally I feel the bite, but it does save me a trip upstairs to turn off the breaker.

Here's where I'm foggy. If the potential is there, but no path to ground... why are the fish affected? I know they are, and have seen the HHL thing on one of my fish when I first started in the hobby. But why is it an issue?

And on another note, the other day when my pump went out and I started feeling the shock... none of my fish reacted to it. Why is that? Coral and fish were perfectly (on the surface) unconcerned with the current in the water.

allan
Thu, 27th Jan 2011, 09:48 AM
Uh... steven, I'm not certain I understood you. Electricity, like water, seeks the path of least resistance to ground. If you have two lines and one is a positive wire and the other is the neutral... you can touch either one of them all day long and not feel a thing unless you are suddenly the path to ground. The lizard traveling on one wire will not be a path to ground at all because he isn't standing on the other wire at the same time.

If you take two wires of a line that is plugged into an outlet you will have the potential of about 115 volts (and the associated current). Just potential. You can actually touch either of the wires individually. But you can't touch them simultaneously. If you touch them together you have sudden path to ground which will register at your breaker box as an increase and pop.

Then there's the other aspect to electricity that makes it dangerous... and a little foggy here as well on the cause. If you are hanging from a wire and not touching anything else in theory you would be safe. However, if electricity potential is there and seeking ground it can jump from your body to the other line or to the earth. This is what happens when folks lose their feet or a hand where the electricity attempts to find ground. Always there is much burning.

Here's the foggy part. Does a power spike in the line become a requirement for this to happen? Why would it happen to Joe, but not Sam when hanging from a single line? Does distance play a factor? Humidity? An electrical storm? Power surge? Luck?