stray voltage

[mantis32]

I first heard about stray voltage at a members house when I was buying LR. I forgot how he was able to tell w/out any equipment. I looked it up online today and found this
http://www.drsfostersmith.com/Produ...en_Page-_-Maintenance&subref=AA&N=2004+113763

How could putting a rod in your tank and plugging it into the wall solve the problem? I must have been asleep in physics the day they discussed this.

 

[JohnS_323]

Actually, it only plugs into the ground part of the outlet. The 2 flat prongs are made out of plastic and are there just to hold it in place. The outlet needs to be properly grounded.

They actually work really well, the only thing is that they have to be relatively close to the offending source of the current. Of course, if you know what that is, you can just remove it! In my case, I have 4 heaters in my sump. I'm pretty sure one of them is responsible for stray current but I'll be darned if I can figure out which one. I put two of those probes in the sump near the heaters and the voltage was greatly reduced.

One way to find stray current is stick a finger with a small cut in it in your tank. There's a little salt water sting but you can CLEARLY tell the difference between that and getting zapped. I'm not saying to go out and cut yourself intentionally, but trust me, if you have a stray current and a cut you don't know about, you'll know about it!

 

[mikem]

It doesn't solve the problem which is a current leak. It redirects the current back to the outlet and makes the water safe for you and its inhabitants. The broken fault is still there.

 

[DaveK]

It doesn't solve the problem which is a current leak. It redirects the current back to the outlet and makes the water safe for you and its inhabitants. The broken fault is still there.

This is an excellent point. The problem still must be found and corrected. I've usually had problems with powerheads and heaters, so I'd check them out first.

 

[Treadingwater]

I found out about my Hydor leak (the second one) when I was cleaning the tank and leaned back against a metal support pole in my basement. As soon as I grounded out to the pole I felt the charge run up my arm that was inside the tank. I now make it a daily check to place a finger in the water and then touch the pole to see if anything is leaking voltage. I'd rather find out I have a problem and remove and replace the source then to leave it there with a grounding probe.

As for finding the faulty piece of equipment, I had my son unplug and replug in each piece while I kept my hand in the water and once I felt the tingling stop I knew we found the source of the problem.

 

[JohnS_323]

Yeah, you're all correct and if I could find the culprit I'd remove it. The thing is really elusive. I've had it "identified" and removed 10 times already, only to find that I pulled the wrong thing. I've unplugged everything and then plugged them back in one at a time only to find that nothing is giving a stray volt. 2 days later, zapped again. Believe me when I say I've given this more than the old college try and haven't been able to locate the source.

It's a real pain, I keep looking for it but in the meantime, the ground probe is at least minimizing the impact.

 

[mladencovic]

In my case, I have 4 heaters in my sump. I'm pretty sure one of them is responsible for stray current but I'll be darned if I can figure out which one.

Wouldn't the simple elimination technique work to find out which. Specially these (hot)days when you do not need all for of them running at the same time.

One way to find stray current is stick a finger with a small cut in it in your tank. There's a little salt water sting but you can CLEARLY tell the difference between that and getting zapped. I'm not saying to go out and cut yourself intentionally, but trust me, if you have a stray current and a cut you don't know about, you'll know about it!

That reminds me of that famous news stroy that got Pulitzer prize "XYZ wanted to check with a match if he still had enough gasoline in his car's tank. Ha HAD a wife and two children"

Wouldn't 15$ voltmeter bought ate Radio Shack or Home Depot serve better? You ground one probe, and then move the other around your tank/sump. Strictly speaking, since salt water is good conductor, depending on the type of a leak you might not see the difference, but then you might if you bring the probe really close. In any case, you will be able to quantify how much of voltage there is between any two points in the tank and see if you need intervention.

This is an excellent point. The problem still must be found and corrected. I've usually had problems with powerheads and heaters, so I'd check them out first.

The funny thing is that with the pumps and powerheads it might not be corrected. The leak might not be real leak from a hot wire, but an induced volatege in any conductor. The pumps are based on more or less strong alternating magnetic fields, and while I am sure that those who made them were probably very careful about voltage leaks, they probably didn't care much about the magnetic fields surrounding them. Come to think, the aquarium water is a giant conductor and any alternating magnetic field in it is bound to generate some ions and stray electrons. I have to figuer this out and come up with some cool experiemenst for my kids this weekend

 

[Carlo]

<snip>

The funny thing is that with the pumps and powerheads it might not be corrected. The leak might not be real leak from a hot wire, but an induced volatege in any conductor. The pumps are based on more or less strong alternating magnetic fields, and while I am sure that those who made them were probably very careful about voltage leaks, they probably didn't care much about the magnetic fields surrounding them. Come to think, the aquarium water is a giant conductor and any alternating magnetic field in it is bound to generate some ions and stray electrons. I have to figuer this out and come up with some cool experiemenst for my kids this weekend

"Ouch dad that hurts", "I don't care, put your finger back in the tank!"

 

[mantis32]

Jack 'treadingwater' you're the reason I started this post b/c I own a Hydor Koralia also. It was at your house buying the live rock where I first heard about stray voltage. I don't know if I have the problem, so if anyone has any cuts and wants to 'heal' their cut in my tank, please feel free to stop by as I don't have any metal posts to hold. Where did I put that knife...

 

[malulu]

i think it probably better to get a testing meter to do a proper test instead of the finger method. (daily or weekly depends on your schedule)

at normal time:
the ground probe should be in the tank at all time - in case the equipment problem occurred, cause we would not know when it will happened.

at test time:
unplug the ground probe to test - with the meter, when done, plug the ground probe back in.

MHO.

 

[mantis32]

It's a good HO. Are you saying go with a voltmeter or what test meter do you suggest? And what level is acceptable and what's not given that I'm sure each device is going to create some sort of field.