Ground your tanks!!!

[phergus_25]

I gt the spur to take the volt meter and test the tanks around the house, and I was kinda worried after I saw what was goin on. My tank had 20 volts and the highest tank in the house was over 50 volts. So being too cheap to buy a ground for each tank i thought and came up with this DIY ground that is SW safe.

 

The part in the tank is one of the wires on an egg wisk, they are stainless steel and I would think tank safe. Next is a peice of stainless steel wre that is next connected to some coaxl cable and stuck in the ground part of a power outlet. I covered the actual power parts with a peice of electrical tape. The volts are down to nothing.

[phergus_25]

BUMP just want everyone to see this so they can do it if their tanks have stray voltage. IF there is a problme with it then tell me so I can take it out of my tank

[RandyO]

Electrolysis is a known problem in salt water. We have used sacrificial "zincs" for ever to keep corrosion isolated to a specific item. I know of no adverse affects for a salt tank however. Have you noted any items "melting" away on your tank?

 

Maybe someone with more knowledge about this can chime in but I doubt that grounding the tank is necessary or even recommended. Grounding could turn your tank into an active battery instead of just a potential battery. (batteries outgas when active).

 

As sandbeds already contain hydrogen sulfide in the lower strata, I do not think I would want to run the risk of pushing it upward (will poison the tank)

 

I think I will leave mine alone until a bit more data is made available. (That is unless my fish start blinking off and on at night keeping me awake)((well except at Christmas))

[RandyO]

A bit of follow up:

 

The primary products of electrolysis are chlorine gas, hydrogen gas, and sodium hydroxide solution (commonly called "caustic soda" or simply "caustic"). However, if the electrolyte is maintained at a pH of 6.5 or 10, one can form chlorate or hypochlorite from the electrogenerated chlorine and caustic. This is the basis for the electrolytic production of sodium chlorate or sodium hypochlorite (commonly known as "bleach").

 

http://electrochem.cwru.edu/ed/encycl/art-...t-b01-brine.htm

 

With this in mind, any level of clorine release I think would be unacceptable.

 

I would remove your ground unless you can find a good reason to have it in the tank....

[doncb]

This is interesting. (BTW: I checked my tank and got 3.4vac water to ground.) A check between ground and neutral gave me 1.4vac of backfeed so the tank was actually at 2vac Probably inductance from the 2 PH's. Part of your reading could be backfeed through the ground. Fluorescent lights are bad about that. Also, if your ballasts are mounted in your hood there could be a lot of inductance unless they are solid state ballasts.)I think I'd install a GFIC just to be safe though.

 

From this link: http://www.thekrib.com/Marine/grounding.html

 

electrified aquarium

by daleman/ccrs.emr.ca (Paul Daleman)

Date: 23 Jan 92

Newsgroup: rec.aquaria

 

I read with interest comments from

laurence-at-cco.caltech.edu (Dustin Lee Laurence)

regarding electrified aquariums. I also once read a magazine article on this

subject (FAMA Oct 1990, p62). As an electrical engineer, I think I'll throw

in my opinion on this subject.

 

Adding a ground to solve the problem of electricity leaking into the water is

not the right to go. It may save the owner from being shocked, but it will make

things worse for the tank inhabitants.

 

The problem is not the voltage level of the tank, but current flowing through

its occupants. Just as birds perched on a high voltage hydro wire don't notice

their bodies are 27,000 volts above ground potential, the same is true in an

aquarium. If one appliance is leaking electricity, but there are no paths to

ground (a glass or acrylic tank is a very good electrical insulator), then no

current will flow, and the fish would not know that they were not at ground

potential.

 

Thus everything will be fine until a grounded electrode is placed in

the tank. Now AC current will flow between the bad appliance and the ground.

This is how people are electrocuted in a bathtub when a radio or hair drier

plugged into the wall falls in. Current flows between the appliance

and the drain pipe (which is a good ground). If the victim's heart is in the

path of enough current flow, it will stop beating.

 

Since the conductivity of salt water is much higher than tap water, it would

probably be harder to electrocute marine fish. The fish will not enjoy

the current passing through its body though. Long term exposure to

even minute currents is probably not good.

 

On the flip side of this, the electrode grounding the tank will protect the

owner better, because most leaking current will flow through the electrode

(the least resistive path) and not the owner.

 

The solution to the electrified tank problem is to find out which components

are the culprits and repair or replace them.

 

I think it would be a good idea for owners to periodically check their tanks for

electrical leakage. The easiest way to do this is to put a voltmeter (AC)

between the water and ground (a good electrical ground - eg wall socket ground).

If you get a reading of more than a few volts, I would worry. **SEE NOTE BELOW

ON VOLTMETER**

 

I don't think it is necessary to set up an elaborate system to

protect you and your fish from electrical malfunctions. Hopefully it is rare

that a component leaks electricity into the tank. A shock from a fish tank

would not likely be fatal, but if it is strong enough, it will cause

an uncontrollable desire to remove one's arm from the tank as rapidly as

possible. This is where serious injury and damage to the tank / hood etc. could

occur.

 

If you want to make a shock-proof tank, hook all accessories that could possibly

cause a problem to GFI sockets (Ground Fault Interrupters). Then hook an

electrode from the water to one of the GFI ground terminals. If anything

begins to leak, the corresponding GFI will cut off power.

 

**A NOTE ON VOLTMETER READING OF TANK POTENTIAL**

When I first tried to measure the voltage of my tank I was surprised to get a

reading of 32 volts. By selectively turning off my equipment I determined

that every electrical piece of equipment near my tank would cause this

potential. It turns out this was because I was using a very high impedance

electronic voltmeter. The tank water acts as an antenna and picks up the 60 Hz

electric field transmitted by nearby appliances. Because the water is so well

insulated, the reading given by a high impedance voltmeter will be

extraordinarily high. The current that the tank can supply at this voltage is

EXTREMELY small. I then connected a 100k Ohm resistor between the tank and the

ground -- the voltage dropped very near zero. If the problem was a faulty

appliance, I would expect no change in the voltage reading with the addition of

a resistor that large.

 

SUMMARY

- If you are worried about both you and your fish being shocked by electrical

aquarium appliances, use GFI sockets and a ground electrode. There are a few

aquarium related products out there that will do this for you if you don't like

wiring.

- If you are just worried about yourself (or can't afford/be bothered with

GFI's) then ground the tank. You will know you have a problem when your fish go

nuts or die.

- If you haven't had a good shock in the last few years and can't be bothered

with this grounding stuff, you can probably get along fine without it. If you

ever get zapped though, don't come running to me!

 

-- Paul Daleman -P.S. I'm leaving my tank ungrounded for now...

[DiverDave]

My two cents worth...

 

$12.50 for a ground probe and $9.95 for a GFCI adaptor that plugs directly into your 3-prong wall outlet. For goodness sakes that's less than the price of 90% of the corals purchased at your average lfs! NEVER operate any electrical equipment without a GFCI when water is involved. Additionally, a GFCI operates by switching off the electrical source when a certain level of current is 'seen' at the ground connection. While induction from nearby electrical sources may read in so many volts, I suspect that the amperage is extreemly low. Current involves voltage and amperage. That having been said, nearly all electical appliances for aquariums are TWO PRONG. As stated above, glass and acrylic tanks do make excellent insulators. My personal experience involves having my hand in a glass tank that had a shattered heating device in it. This was at a mom-and-pop fish store. Even though my hand was in the tank with a 120V line IN THE WATER there was no path to ground...until I touched the metal rack. The rack was connected to metal water pipes, and as you know, water pipes go straight into the GROUND. My saving grace was that the electrical system, also metal and connected to the rack, had a GFCI on it and while water pipes make excellent grounds, electrical boxes are better. I received one hell of a zap and, fortunately, the GFCI poped the circiut in less time than it took me to figure out what damn fish bit me! If a ground probe had been installed in the tank, the circuit would have tripped the moment that the glass case of the heater was compromised. Unless you have a severe electical problem with your tank, any induced voltage that finds it's way to the GFCI through a ground probe is no where near enough to trip the protection circuit. As a kid or adult, how many times did you test a 9volt batery with your tounge? 9Volts, very little amperage. Your car has a 6 or 12 volt battery yet it can start your vehicle; lots of amperage. I agree that an electrical current in water will cause chemical changes that can produce molecular changes in the compounds when enough current is applied. My feeling is that the amount of current/released potential energy from our tanks through a ground probe is so small that any chemical differential would be undetectable and most likely short lived by the tanks ability to 'buffer' its self. We probably induce more electricity into the tank through static electicity formed by the bubbles we create in our skimmers. (Which, as you know, the electical differential in the protiens and waste products we remove via a skimmer require a bipolar charge in order to attach to the bubbles...but I digress)

 

Get a GFCI if you dont have one already and use a ground probe.

[Pinchy]

one guy who frequently visits our store had a long standing tank but has experienced coral trouble- after weeks of trying to figure it out- i finally asked him if his tank was grounded... he said no- he bought a 12 dollar grounding probe and in the next day his corals began look much better-

[phergus_25]

Yea I know they sell probes for tanks So i figgure it is a good thing. And since my tank went from 20 volts to 0 volts I think it is a good thing. just thought I would throw it out there so everyone can decide for them selves but I'm going to leave mine in.

[BKtomodachi]

BTW, stainless steel will often rust in SW. Its okay to use temporarily, though.

[phergus_25]

yea I turned the cut portion up so only the no cuy part is in the water, so if it gets to rusting I will change it.

[Daemonfly]

One thing you can try is grounding your lighting reflector (if it's not already). I've noticed that even with 1 55w PC bulb, the reflector can give quite a decent shock (i.e. burn marks if the point of contact is small enough point). Usually happens more with the higher frequency electronic ballasts, IME.

[RandyO]

Originally posted by BKtomodachi

BTW, stainless steel will often rust in SW.  Its okay to use temporarily, though.

only poor grades of stainless will rust (low nickel/chromium content). I have dive knives that show this, my cheapy $40 ones will rust and my high grade knives with the higher grade alloy never even water stain. Get high quality marine grade stainless fastners and you wont have rust problems.

[phergus_25]

ok thanks

[RandyO]

I think the opinion of an electrical engineer takes a bit more weight over that of hobbyist.

“I think my fish look better” is another pretty non-scientific statement.

 

Just because they make a tank ground does not mean it is a good thing. Purchasing items under the assumption that "if they make it and sell it , it must be a good thing" is a pretty dangerous premise to base a decision to use that product.

There are hundreds of products I could cite to reinforce this statement but I think if you give it a second, you can think of 1 or 2.

 

This is actually a pretty old issue and nothing new, it has been discussed and it appears that some hobbyist feel better having it, whereas professionals, and commercial tank keepers seem to think it is either “of no benefit” or even detrimental to the tank environment.

 

I will side with them on this one.

[phergus_25]

Ok, I admit defeat, you win RandyO... Ha Ha. Well after reading your statments again and reading on RC I decided that it was more of a potential for harm than somethign for good. Well Needless to say I have removed my probe.

[RandyO]

It would be interesting to do a control study on this. Just not sure how you would go about it yet.

[phergus_25]

ha ha yea I dont know if I want to get shocked or shock any fish. I thikn that the probe could save me but it would be a bad thing to my fish and corals. So I'll leave it out. Hey if some thing is wrong I can take a 110 volt shock once.

[10" Red Devil]

Where can I pick up a GFCI Adapter? The hardware store? So I also would need a ground that one part goes in my tank, and the other goes into the adapter as well as all the plugs for any elctrical device in the water?

 

Thanks!

[RandyO]

Originally posted by phergus_25

ha ha yea I dont know if I want to get shocked or shock any fish.  I thikn that the probe could save me but it would be a bad thing to my fish and corals.  So I'll leave it out.  Hey if some thing is wrong I can take a 110 volt shock once.

Get a GFCI adaptor. No reason to put yourself at risk and it is a good idea for that "Just in case" part of life.

 

10" Red Devil, hardware store or any place that sells electrical outlets. I am not sure these are sold as regular adapters as my outlets themselves are GFCI protected. As with any thing electrical, if you are not sure what you are doing, find a pro.

 

Changing wall outlets is pretty simple but can still get you hurt or killed if you do not know what you are doing.

[vangvace]

the lfs around my house sell gfci adapters for $20. If you know how to wire sockets it's cheaper to buy the whole outlet from Lowes though.

If you place is newer (last couple years built or renevated) you may already have the gfci outlets or circuit breakers. From what I understand they are manditory for kitchen/bath now.

[DiverDave]

Champion Lighting and Supply at www.championlighting.com sells a GFCI unit that will plug directly into your existing 3 PRONG electrical outlet for $9.95, and, if you desire, a titanium grounding probe for $12.90. You would plug the GFCI into your wall and then run your power strip(s) off of its outlet. (All 3 PRONG outlets that are attached through the GFCI will be protected.) The ground probe is designed to plug into a regular 3 PRONG outlet. I found a double GFCI plugin unit at the HOME DEPOT store.

[Pinchy]

phergus- can you tell me why a grounding probe would be a problem to corals? b/c ive got one now and i dont wanna cause any issues.

[phergus_25]

http://reefcentral.com/forums/showthread.p...nding+your+tank

 

Well basicaly is goes to a bird standing on a electrical line. This is ok unless the bird goes and somehow touches the ground the circut is compleated and *POOF* a ball of burning feathers. So basicaly I'm going to replace my rio pump as soon as possible and make shure that was my only problem. And since my corals look great I suppose the electricity isnt a big problem. But if your tank is filled with current and you put your hand in get ready for one hell of a shock.

[Pinchy]

thanks phergus- i just took mine out-

[dannyzzz]

I would like to add a small bit of information about stray tank voltage. In salt tanks, through time salt can accumulate in some unwanted places, including around light fixtures. Salt can conduct electricity. I recently heard of an example of this conduction. I was at a local reef store and we were discussing the fact the a whole section of tanks was shocking anyone putting their hands in the tanks. When troubleshot, the final outcome was that a salt trail had developed from a ballast and since the tanks water supplies were interconnected, all were charged.