PlanetCatfish.com

Dr Frankenracoll

MatsP wrote:

Kostas wrote:Thank you very much for your reply

So the volts shown dont exist and are a ''bug'' of the voltmeter or do they actually exist but are only seen through difference in voltage between the tank and a neutral object?

The voltage is definitely there - but only because you actually have the metal in the tank - if you didn't have the metal there, there would be no voltage.

I think i got your point... In other words you say that if racoll havent putted his hand in water,the fish wouldnt have been hitted by electricity although the heater had leakage,right?And the same with grounding,if the equipment isnt well insullated somewhere and is leaking electricity and the aquarium is not gounded,fish wont notice this leakage,while if the aquarium is grounded,they will get shocked by electricity,right?

P.s.:Sorry racoll for using your bad experience as example

Thank you very much in advance

Entirely correct - if you have a ground-post in the tank, then the electricity will flow from the "leak" to the ground-post. With no ground-post, there's nowhere the electricity can go. If you have a RCD, it will "detect" the fault and cut the power, so:
1) You can safely put your hands in the tank.
2) Fish won't be able to fry themselves on the electrical bits (say if there's a big hole in the glass of a heater or such).

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Mats

Mats sayed it correct

apistomaste wrote:

MatsP wrote: Probably the same mong's that come up with magnets that you can put around your water pipes "to align your calcium ions so that they do not form scale in your kettle". I.e. it's something people don't understand and can't see if it "works or not", so they buy it based on what it says that it does.

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Mats

Now be careful, Matt, I know that works because I have seen them advertised in tropical fish magazines. evil Darned Hypno Toads. And if my perpetual motion machine would turn on I couldn't turn it off.

apistomaster: Your joking or aren`t you

Thank you very much all of you for your replys

Still havent completely understood two things:is there any voltage present in the tank,as the voltmeter show, and if yes,would this negatively affect fishes long term?
When there is a leak and there is no grounding,will fishes be shocked or not?On the other hand,if there is a leak and we do have a grounding probe in the aquarium,will this prevent fishes from getting electrocuted or will this actually make them get hit by electricity?(thats why i asked you if you saw your fishes getting shocked when you got electrocuted racoll...was it a strong one or light one?I have got electrocuted too by the lighting fixture of my Rena aquarium...but it was not very strong...still i was a bit shaking afterwards... )
By the way racoll,the Rcd may had detected a light leak from the heater and thats why it tipped...I dont think that everything was fine then,it may just had been a very light leak or a short duration one

Thank you very much in advance

If the tank is grounded, then the current will flow from any faulty equipment to the ground-post. I don't believe it will affect the fish much in either case.

As to your "measured voltage", it's there because you are trying to measure it. If you stick any metal in the tank, you are essentially creating a battery-cell. Depending on which metal, and the conditions of the water, this may be a higher or lower voltage battery, but it's a sort of battery either way. This is what you are measuring.

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Mats

was it a strong one or light one?

It wasn't a strong shock. Not as bad as the time my friend dared me to touch the electric spark starter on the gas hob. OUCH.

By the way racoll,the Rcd may had detected a light leak from the heater and thats why it tipped...I dont think that everything was fine then,it may just had been a very light leak or a short duration one

I am pretty sure the incidents (the tripping RCD and the electric shock) are not related.

I shall try and explain a bit more clearly....

racoll returns from work and finds tank cold with all filters, pumps, lights off. The RCD has tripped. racoll, worried about his fish, now takes RCD off the power supply. Everything works fine from now on.

A couple of months later....

racoll performs water change and accidentally melts heater. racoll thinks heater is fine and puts it back in tank. An hour later, racoll feeds fish and gets electric shock. racoll replaces heater and all is well.

Does that make sense?

Who is this other racoll of which you speak?

Is it a clone that you contrived to life within a vessel of water, stitched together from various transient parts then put an electrical current through generated by the electromagnetic motors in the tank, and now it goes around sabotaging your aquaria?

Dr Racoll and Mr Hyde........

Thank you very much for your replys

Mats,
Ok,now i understood that about the measured voltage!Thank you very much So a grounding to start with is not necessery as there is actually no voltage presesnt in the tank...
I asked that about the grounding and the leaking because racoll said his fish too were hitten when he was electrocuted...

racoll,
Yes,it pretty it pretty much makes sense now I was missing that the heater melted...

I notice that if I have cut on my hand I feel a very slight electrical tingle on the cut when I place it in the water of my tanks, is this a sign of a fault of some sort in my electrics? or is it normal?

I have noticed this too but I thought that it was the pollutants and bacteria in the water stinging my exposed flesh, but now you come to mention it it does feel like a shock.

Anyone on that?I have heard that from others too and i wonder,if there isnt normally electricity in the water,why does this happen?Is it the same with the voltmeter thing?In this case we are not having neither two probes nor a metal in touch with the water...

Thank you very much in advance

I think Matt is right, bacteria and pollution will give a stinging sensation, similar to that of electricity. You will not feel a few volts anyways - unless it's VERY strong current too. A small current at high voltage will be "felt" - at work many years ago, my collegues wired the door-handle with 400V/16uA from a "backlight unit" for a LCD-panel. That stung a bit if you touched it lightly, but if you took a firm grasp of the handle, it couldn't be felt.

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Mats

I agree,bacterias and pollutants do give you that sense...The reason i asked is because i have never felt what they say in my aquarium as i try not to place my hand in the aquarium if its just injured and place the other one instead On the other hand,i do have experienced that stinging effect when placing my injured hand in not so clean water and when dirt falls onto an injury...Never thought of that as electricity because there is no chance it could be from electricity...
But that about sensing a small voltage in the water,i dont know...I have heard that if you lick the two poles of 9Volt battery,you sense the voltage with your tonge...Never done so i dont know if its true or not...If its true,there is some chance you could sense it in water with an injury...
What do you think?

I have heard that if you lick the two poles of 9Volt battery,you sense the voltage with your tonge...Never done so i dont know if its true or not

I can confirm this.

The stuff you do as a kid

You could of course try it, if you don't believe Racoll. I have done it as a kid too (and with the big 4.5V ones). It stings a bit - particularly if the battery is "fresh". But it's harmless enough. Not the same with 230V AC that is in the house!

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Mats

Thank you very much for your replys

Ok,so if you confirm that,wouldnt there be a chance to feel a small electric current through a small injury?I ask that because,exposed flesh has less resistance and as we know electricity follows the easiest path...The same with our tongue,smaller resistance...

What do you think about that?

P.s.:I too used to play with batteries when smaller,i was particularly fond of the big 9V ones and the big 4,5V you say...Because any experement had more obvious results,i.e. if you connect small wire and connect the two poles,you have a wonderfull fire...

Thank you very much in advance

Yes, but you also need a "ground" somewhere, and assuming you don't also have a conductive carpet and a cut in your foot, nothing will happen.

Ever seen birds sitting on the power lines? That's thousands of volts and many amperes - strong stuff, ok. But since the bird is not connecting to anything else, it will not feel any of the electricity.

--
Mats

Thank you very much for your reply Mats

Yes,but then why racoll was shocked?He most probably didnt had a conductive carpet and was wearing shoes...Isnt the difference in voltage between water and our body enough for us to be a temporary ground?

I know that about birds,its exactly the reason you said...

Well, with 220V, it will still flow enough current through your body to notice with your average floor having some conductivity, and NOT using Wellington boots or thick rubber sole shoes.

--
Mats

Thank you very much Mats

I have discontinued the use of grounding to my aquariums...Will see if i will use Rcds instead...

Have you tried testing for a current with everything switched off?
Matt

grokefish wrote:Have you tried testing for a current with everything switched off?
Matt

Doesn`t matter. The voltmeter shows someting, as sayed, becouse you put metal in

I don't know how big the EM fields produced by pump motors and heaters are, but I do know those produced by flourescent lighting are measureable. You can't however measure them with a standard voltmeter, it takes special equipment. Grounding a tank will bleed off any potential produced by an EM field but it will also set up a situation where low current levels may be present whenever your equipment is on. I don't know if anyone has done any studies to see if this is detrimental to fish health. I do know that long term exposure to low level ground currents can damage electronic components. I also know that lightning creates massive EM fields. In an ungrounded tank, no big deal. Grounding a tank could produce a scenario for a very short term but substantial ground current. I don't know if anyone has studied this either but I wouldn't think it would be good for the fish.

Hi grokefish,
No,i havent done that...In fact,i have never tested for voltage in my aquariums I have only tested for voltage the tanks of the Lfs that first told me about the ''neccessity'' of grounding...I dont remember to take off the equipment plugs from any of the aquariums i tested...I only took off the grounding and it showed some amount of electricity(6-9V,not more than that but i dont remember the exact numbers) and then when i replaced the ground it showed 0V...(By the way,i didnt bought a ground at that point,i returned and did my reasearch and because i found some articles stating some said to be facts about the benefits to the fishes of having a grounded tank,i went to another shop and bought the Rid-Volt product...)The reason i havent measured my tank and havent done what you say is that although i do have a voltmeter,its horribly dirty,so much that even after cleaning it,i wouldnt dare to put its electrods in my aquarium But i may go buy another at some point,especially when i have the 2meter up and running to see what it measures just out of curiosity...

Hi Durlänger,
Thank you for your reply
Is what the voltmeter measures when placed in the tank always completely ''fake''(when you have the equipment running i mean,not without the equipment) or does it also shows some voltage that does exist and after taking it off the tank?If you dont have a ground,does this voltage potentially annoy fishes or it doesnt exist because it has nowhere to go?

Thank you very much for your reply rahendricks
What you say is very interesting and also strongly suggests that its better for fish to not ground a tank...

So i now think that you all agree that aquarium grounding is dangerous instead of doing any good...

Thank you very much in advance

Kostas wrote:
Is what the voltmeter measures when placed in the tank always completely ''fake''(when you have the equipment running i mean,not without the equipment) or does it also shows some voltage that does exist and after taking it off the tank?

1. If you put only one cable from the voltmeter to your tank - then it`s telling you "something or bullshit or maybe the last thing it remembers" as it has no comparison
2. If you put two cables dirctly into your tank - it measuers the difference between the potentials of both metals under your tank condition, 0V if both cables are exact out of the same alloy
3. If you put one cable into your tank and conect the other one with the grounding - then a.) you will see the difference between potentials of cabel and grounding b.) I will be very very angree with you as you still have a grounding But I wouldn`t show you as you cann`t see me
If case 2. or 3. shows you something fluctuating or nothing - then I have to say that normally we use a galvanometer (simulare to a voltmeter, http://en.wikipedia.org/wiki/Galvanometer , shows +V aswell as -V), with 3 or maybe more inputs so it´s possible that a voltmeter doesn`t have the right inputs

Thank you very much for your reply

So in other words,both 2 and 3(for the one is obvious ) are fake or is 3 more accurate?As i have said in a previous post of mine,i have removed the grounds from both of my tank But of course its not difficult to put back on one again to do the 3rd you said when i buy a new Voltmeter...

I cant understand your last phrase very well

Kostas wrote:So in other words,both 2 and 3(for the one is obvious ) are fake or is 3 more accurate?

Not fake, it´s made by putting two conected metals into the tank, so it isn`t there normally

Kostas wrote:As i have said in a previous post of mine,i have removed the grounds from both of my tank

didn`t notice that

Kostas wrote:I cant understand your last phrase very well

Well selecting the right word out of the dictinary isn`t very easy
fluctuating = changing
the link I gave for galvanometer is more for someone who is really interested in electronic measument, I hoped that the Greek version would be understandable
input = the part (of the voltmeter) where the cables can be put in
the whole last phrase = I´m not really sure, but I think, that a voltmeter can show that. The thing we use instead called galvanometer knows if it measurs +123mV or -123mV, a voltmeter doesn`t know that. As both show V I forgot the mention that I talked about a galvanometer instead

Did things get clearer

edit: whole instead of hole

I "ground" all my tanks with stainless steel probe (connected to the earth of the power socket) submerged in the water.
That's becos I hate the biting sensation I get sometimes when I put my hand into the water during cleaning. The weak leakage can come fm the tank light or powerhead esp when it gets old.