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Posted: 11 Sep 2007, 09:42
by Kostas
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 :)

Posted: 11 Sep 2007, 09:50
by MatsP
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.

--
Mats

Posted: 11 Sep 2007, 10:18
by Kostas
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 :wink: 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?

Posted: 12 Sep 2007, 11:00
by racoll
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 :roll:

Posted: 12 Sep 2007, 11:08
by MatsP
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!

--
Mats

Posted: 12 Sep 2007, 12:11
by Kostas
Thank you very much for your replys :wink:

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... :lol: :roll:

Thank you very much in advance :)

Posted: 12 Sep 2007, 12:28
by MatsP
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

Posted: 12 Sep 2007, 12:39
by Kostas
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... :wink:

Posted: 12 Sep 2007, 12:47
by MatsP
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

Posted: 13 Sep 2007, 09:00
by Kostas
Thank you very much Mats :D

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

Posted: 23 Sep 2007, 19:15
by grokefish
Have you tried testing for a current with everything switched off?
Matt

Posted: 26 Sep 2007, 14:46
by Durlänger
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 :!:

Posted: 26 Sep 2007, 17:34
by rahendricks
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.

Posted: 26 Sep 2007, 17:50
by Kostas
Hi grokefish,
No,i havent done that...In fact,i have never tested for voltage in my aquariums :oops: 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 :lol: :roll: 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 :)

Posted: 27 Sep 2007, 17:03
by Durlänger
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 :wink:
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 :evil: :evil: :evil: But I wouldn`t show you as you cann`t see me :wink:
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 :roll: :roll: :roll:

Posted: 28 Sep 2007, 07:52
by Kostas
Thank you very much for your reply :D

So in other words,both 2 and 3(for the one is obvious :lol: ) 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 :wink: 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 :oops: :roll:

Posted: 28 Sep 2007, 14:20
by Durlänger
Kostas wrote:So in other words,both 2 and 3(for the one is obvious :lol: ) 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 :wink:
didn`t notice that
Kostas wrote:I cant understand your last phrase very well :oops: :roll:
Well selecting the right word out of the dictinary isn`t very easy :roll:
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 :roll: :oops: :(

Did things get clearer :?:

edit: whole instead of hole :roll:

Re: To ground or not to ground?

Posted: 18 Aug 2022, 12:30
by amiidae
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.