Very Weak Shock

Matt1997

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Sep 18, 2017
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Barrie/Sudbury
I find when I put a finger in the tank with a cut I receive a very faint sting. When there is no cut on my finger I feel nothing. The slight shock seems to be produced by a combination of both the skimmer and return pump. The pump is a vectra m1 and the skimmer is a vertex alpha 200I. Is this a concern?
 

Luke.

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Jun 9, 2015
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When I first got in the hobby I had something weird like that , and bought one and didn’t notice it anymore , I’m not sure it was cheap to try lol
 

Reef guy

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May 1, 2020
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London
Mine is doing the same thing but only in my sump not my main display tank it’s weird from what I was told there is a short in one of the wires I don’t know if it’s true or not
 

TORX

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I would double check with a volt meter on which device is doing it through process of elimination checking for a current in your tank. You are correct about the ground probe. It does redirect the current which could be life saving, but it also masks any issues that may arise. If you end up with a bad short and your probe gets unplugged or something, prepare for a major zap. You definitely want to figure out what it is and replace it before it gets worse.
 

Winks

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If it is stray voltage, it won't get better by it's self it will only get worse.
 

Salty Cracker

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I've always been against grounding probes, there's some talk that streaming voltage like that can cause HLLE, but of course, what doesn't cause HLLE...

When I first had this issue, it was as Torx suggested, turn off each item in the sump and try the finger. If it's just salt sensitivity it will only happen the first time, if it's voltage it will be every time. Turn things off until it stops, and that's the culprit. Usually it's an issue with the epoxy in a motor, saltwater gets in there and either rusts/bloats the device, and/or it leaks just enough voltage not to trip the GFCI ( if you don't have one, get one, it could save your life!).

For me, the issue was healthy sps turning into very unhappy sps. When the voltage goes up it affects more and more types of coral. stn turns to rtn.
 

Jason Bell

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Apr 3, 2019
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l2r4t1
I'm forgetful of late, so if I stick my finger in the mixing vessel and get a good shock then it reminds me I've added salt. New pump has been ordered :)
 

Matt1997

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Sep 18, 2017
Location
Barrie/Sudbury
Both tanks are on GFCI. I find a slight sting when I put my hand in both tanks. Only occurs on one finger that has a tiny cut. I can’t imagine they both have some type of faulty equipment.
 

Matt1997

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Sep 18, 2017
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Barrie/Sudbury
Oh coarse if it is only present when you have a cut, it could just be the salt water hitting it the cut. That is why I suggest testing for stray voltage with a multimeter. There are videos online on how to do it.

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I’ve watched those videos and all I see is every piece of equipment adds some amount of stray voltage to the water. None gave quantifiable numbers as to what is “not safe”
 

Salty Cracker

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I’ve watched those videos and all I see is every piece of equipment adds some amount of stray voltage to the water. None gave quantifiable numbers as to what is “not safe”
I think that's correct. There can be 'some' stray voltage. Grab a multimeter and see, and if your coral is doing fine, then mark that as your baseline reading. If the corals start to show signs of stress, check the readings again. When my corals started to melt I got something like a static electric or small capacitor shock. I would think the stray voltage would only enter the display tank when you have the return pump running (making the saltwater the conduit or whatever the term would be). I would get a very slight buzz on a cut in the ST, but more in the sump (which makes sense I suppose). This isn't really an exact science, and there's still the group that swears by simply dumping the stray voltage to ground, but to me that just sounds dangerous. You now have current instead of static charge...

I would think the worst ones in the tank to leak would be heaters. Not sure how many amps those things draw but just think...we put electrical heating elements into salt water, and encase them in breakable glass. Add that to the deadly toxin in palys and we must be either really brave or a really stupid bunch :)
 

Josh

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Jan 1, 2017
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The problem with having power in the aquarium is anything that creates a magnetic field essentially creates a "fake" or "phantom" voltage. This can cover up ACTUAL electrical issues. In the same way you measure voltage with 1 lead in the water and 1 on the ground of the plug check the water for Amps. This will create a series circuit to check for amperage. Induced voltage should not be able to create much if any current draw, actual voltage will be a different story. Try measuring the current draw to ground (careful this will likely trip your GFI) and turning pumps/heaters on and off until you see the number drop.

Its a pretty safe assumption its one of your heaters, if you start having a short on a motor it causes the magnetic fields to change and they become unequal, the rotor would start to jam if this was the case, if your powerheads are moving water the likely culprit is a heater.

Good luck
 

Josh

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Jan 1, 2017
Location
London
Oh coarse if it is only present when you have a cut, it could just be the salt water hitting it the cut. That is why I suggest testing for stray voltage with a multimeter. There are videos online on how to do it.

Sent from my SM-G988W using Tapatalk

A cut lowers your internal resistance of your body which makes it so you feel the tingle on less voltage. Voltage is basically the amount of punch the power has, the higher the voltage the more possibility it will jump and go through your body, If you have a cut in water you are reducing your internal resistance and it lets the power flow through you to the ground you stand on. Normally your body resistance just lowered the amount of power flow to the point where you cant really feel it.
 

Salty Cracker

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The problem with having power in the aquarium is anything that creates a magnetic field essentially creates a "fake" or "phantom" voltage. This can cover up ACTUAL electrical issues. In the same way you measure voltage with 1 lead in the water and 1 on the ground of the plug check the water for Amps. This will create a series circuit to check for amperage. Induced voltage should not be able to create much if any current draw, actual voltage will be a different story. Try measuring the current draw to ground (careful this will likely trip your GFI) and turning pumps/heaters on and off until you see the number drop.

Its a pretty safe assumption its one of your heaters, if you start having a short on a motor it causes the magnetic fields to change and they become unequal, the rotor would start to jam if this was the case, if your powerheads are moving water the likely culprit is a heater.

Good luck

It's so much better when smart people explain things properly :)
 
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