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danny2013
06-26-2010, 04:45 PM
Would 2 volts of electricity in my tank make my discus panic or make them stress?

decula
06-26-2010, 05:49 PM
Would 2 volts of electricity in my tank make my discus panic or make them stress?

hate to answer with another question, but what did you measure the 2 volts with?
if it's about a heater, are you measuring on AC with an accurate RMS meter?
And from where to where?

It's possible for an analog meter to totally miss peak voltage on leakage.

The other part of electricity is current - enough available current can kill at
a low voltage.

If you suspect the fish are getting a "tickle", what happens if you unplug the
suspected device for a short period?

I saw a post recently where someone saw moisture inside of a heater, thats
a good reason for replacement ASAP in my book.

dec

Jhhnn
06-26-2010, 06:41 PM
2V is basically insignificant. Low potentials like that exist in all kinds of situations- They can be found all over the house or workplace. If it bothers you that it's there, put a grounding probe in the tank.

50V and up are considered potentially lethal to humans. In my work, I maintain equipment that carries a variety of voltages, up to 860VDC, so I'm necessarily trained and educated wrt that...

decula
06-27-2010, 09:05 PM
danny2013,

this might serve as a good reference:

http://en.wikipedia.org/wiki/Electric_shock

it's not based on Discus, more on humans. Note that skin resistance
changes by a *factor of 100* if it's wet.

Also, all of a DIscus' vital organs are in the tank. It's current that
kills - you just need enough voltage to make it to the vital organs.

Back to the questions - how are you measuring 2 volts, where, and with
what?

dec

decula
06-27-2010, 09:15 PM
and here:

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

Jhhnn
06-28-2010, 07:10 PM
I think decula's question is important- instrumentation and technique are always important. I based my comment wrt 2V potential on the assumption of good technique and instrumentation, which I shouldn't have done.

There's a lot of myth and opinion wrt the use of grounding probes in aquaria, which I really don't want to get into. With the exception of extremely pure water, all of it will pass current to some degree or another. Aquaria w/ faulty electrical components can easily carry high voltage potentials because they're isolated, insulated from ground. It's like a bird on a wire. Everything can work normally, until a path to ground is created, usually through the aquarist. Shock will occur. The severity of that depends on many factors.

The use of grounding probes creates a better ground than the aquarist, reducing shock hazard. If catastrophic failure occurs, the circuit breaker will trip, which may not happen in the absence of a grounding circuit. Electrical leakage in such a scenario would likely affect the fish, whereas it may not if there's no ground and therefore no current. Nonetheless, grounded equipment is safer for human users. The use of GFCI breakers virtually eliminates shock hazards, although they can be extremely touchy, resulting in false trips... which isn't good for the fish, either.

None of my own tanks have GFCI or ground probes because lethal shocks are hard to get w/ laminate floors on wooden joist construction. I might look at it differently if I had tanks on concrete floors in a basement, particularly if I preferred going barefoot...

Any aquarium equipment that delivers a noticeable tingling or shock should be isolated immediately on discovery and disconnected, then discarded, preferably with the cord cut so as to discourage anybody else trying to use it...

Where we live, in a very urban neighborhood, we have alley people. Anything that can be recycled or sold for scrap just disappears when put out in the alley. I've had occasions when carrying out multiple items where I put one down, go back to the house for more, and when I get back to the alley, the first item is just... gone, and there's not a soul in sight... Which is OK, I guess, but it's just... a little weird sometimes.

vstar
06-28-2010, 08:16 PM
A couple of my heaters also showed moisture inside of the heater tube. I took one of them and put it in a 5 gallon bucket with water and plug the heater in. Then took my volt meter, the black probe I grounded it and put the red probe in the water. It showed no voltage leaking from the heater. I don't know if I did this right, but was told I did it right. The fish has showed no difference in them or any sign of problems.

Offpath
06-28-2010, 10:38 PM
A couple of my heaters also showed moisture inside of the heater tube.

If moisture is getting in the heater tube, I'd replace them. If the water hits the heating coils, it can turn to steam, and the pressure can explode the heater. See this thread (http://www.plantedtank.net/forums/equipment/103155-beware-marineland-stealth-pro-heater.html) for an extreme example.

bstreep
06-29-2010, 12:24 AM
Mag pumps (not the brand, all types of magnetic drive pumps) are notorious for stray voltage. The very nature of them creates current - even just a little. When I had my 215 Reef set up, it was enough to give me a tingle (10,000gph of flow...).

What I did was use grounding probes that kept the voltage out of the tank (I located them between the pumps and the tank). Grounding probes are kind of a bandaide on the problem - the don't get rid of it, they just make it safer. If you have fish between the source and the probe, they WILL be affected.

Remember, that electricity takes the path of least resistance (sort of- it takes paths based upon the resistance of those paths - lesser resistance will get more current). So, you want the source to be as close as possible to the grounding probe.