Electrical "Leakage" in a tank??

[andsoitgoes]

I don't know how to better describe the situation, but I was just planning on heading out and I put my hand in my tank to do something or other, and I had a few cuts on my fingers, well - it hurt like the DICKENS

I couldn't for the life of me figure out why, I tried it with other fingers that had cuts, and the same pain. I tested a few other things out, and then I got the same feeling on my OTHER fingers, with no cuts. Pulling the plug to everything made me realize that it was something electrical.

I proceeded to unplug everything, one by one, and I cleaned out some much needing cleaned powerheads, and made sure nnothing was being blocked or running "dry" - I did notice that a few of my PH's in my sump were in rough shape, and I think my pump to the UV unit was fully plugged.

Needless to say, all is done and it's fine now, no "zapping" when putting my fingers in my tank, and all livestock seems okay (might explain why my SPS have fully browned and dying) - and it had nothing to do with my heater, that one never "zapped" when it was the only thing plugged in, and that was one of the first things I tried.

But is there anything else I should worry about? I have a grounding cable on my tank to suck away the excess, I can't imagine what this would have been like without that. Anyone experience this, suggestions, what I should be aware of or watch out for?

Thanks!

[andsoitgoes]

Well, things are not really any better, I have figured out why it was intermittent, though!

I have a spot on the floor that some water spilled on, it's carpet so it holds that water nicely.

when I stand on that and put my hand in tank, zap. Dry, it's fine.

What's going on, what do I do? It's owie and I don't want to kill my tank! :(

[0sprey]

You should install a GFI (Ground Fault Interrupter) on your plug. It's quick and easy to do. When anything starts leaking electricity into the water the GFI will trip and break the circuit. You'll have to unplug everything and plug them back in one at a time to see which appliance is leaking current. Then you can replace the offender.

[andsoitgoes]

That might be an idea, was hoping for reassurance and a warm fuzzy response that all is fine and it's normal :(

Don't know when I'll be able to actually get a gfic or install it, I know they're easy... But it's just a matter of getting out and getting

Ugh, frustrating. How dangerous is a small shock like this?

[Static]

A few articles I've read lately http://reefkeeping.com/issues/2005-06/sp/index.php as an example suggest that grounding probes cause more current flow in the tank, even if the voltage reading seems lower.

If you put a voltmeter on either terminal on a battery that's not hooked up you will read voltage, if you connect the two terminals, ie short circuit them you will read less or no voltage on your voltmeter. What is suggested instead is to find the peice of faulty equiptement and replace it rather than providing a rout for the "stray voltage" to escape.

[mark]

It doesn't take much current to kill (fractions of an amp) and getting a tingle isn't normal.

Should get a GFI and a ground probe as you found all can basically look normal but still have the potential to cause harm. That way in the future when something does start to fail the indicator will be the GFI tripping rather than you flopping on the floor.

To find the device causing the problem, suggest with a GFI and ground probe, unplug everything, then start plugging back in one at a time. What trips will be the device that's leaking the current.

As for the argument that what if I'm away and the GFI trips and the tank crashes. Well, in my case believe (at least pretty sure) the wife would rather the tank crash than me dead.

I've got multi GFI circuits with the idea if I get something like a little salt creep on the lights, it won't take out all the pumps, if the sump return fails, the CL is on another etc.

[deep6er]

I had this problem a long time ago too. . Trying to find what was causing the short was very painfull. And it just so happened that it was the last one i checked. It was my CL skimmer. My suggestion to you is to find what is causing it.

[Static]

You can use a voltmeter to test your equipment. One probe in the tank, and the other in the ground of your wall socket. Simply unplug each piece of equipment until you see 0 volts.

[andsoitgoes]

Having ANYTHING plugged in will cause the voltage to go up, even an incremental amount. I found a few good articles on that here:

http://www.reefs.org/library/aquarium_net/996/996_5.html

however - the biggest factor is that the ONLY time I feel it is when I stand on the "wet spot" on the floor. I move off of that, and nothing.

I had the + wire of the voltmeter in the tank, I took the ground and stood on the spot, the needle moved to a VERY small amount, but it moved. I took my foot off that spot, and all was hunky dory.

How does this make sense?

[Static]

It makes sense because the dry spots on your floor are better insulators than the wet spots. Voltage is the difference of electrons between 2 parts of a circuit. In this case you are making yourself and the wet spot on the floor part of the circuit. When you move off the wet spot you are opening the circuit, like flipping a switch. In other words, when you are standing on dry ground you are no longer grounded, and the voltage is not attracted to you. Is it a wood floor under the carpet or concrete?

Did you check the voltage between the tank water and the ground on your electrical outlet? You should just be able to touch the voltmeter probe to the screw that holds the faceplate onto your outlet.

[andsoitgoes]

I did - I used the 3rd ground hole on the plug to test it. I would get readings that would barely show up when having the meter set to 10V, putting it to 50 would show even less, and then nothing at 250.

The floor under the carpet in that area is straight on plywood.

So is that a GOOD thing that I'm completing the circuit? Should I just stop messing around and leave my gimpy hands out of the tank? ;)

I'm wondering if it has something to do with the direction the electrictal wiring runs, or maybe something got a bit damp under my breeding setup that's in front of the "wet spot"?

[Static]

are you testing for alternating current or direct current? ac or dc on your voltmeter. Any stray voltage will likely be alternating current.

I'm guessing that you were testing for dc, because if there was enough voltage there for you to feel a zap it would likely show up more significantly on your voltmeter. Also if it is simply induced voltage, like the article you posted suggested then it will be ac.

if you haven't already, then try testing for ac, both at the ground on the wall, and maybe the wet spot on the floor. If you get a reading, unplug your equipment 1 piece at a time to find the faulty piece.

And maybe where rubber soled shoes while you're testing.

[andsoitgoes]

It's AC, trust me

ANd I can't reach the wet spot on the floor, unless I'm using myself as part of the circuit.

I've unplugged everything, and put it back in once at a time, testing before and after - the SECOND I plug anything in, I get some minor current.

Again - the zap is happening only on the areas I have open cuts on (i was doing work outside and cut the heck out of my fingers)

When I hold the ground with the + in the tank, and stand on the wet spot - It shows on the voltmeter, but a VERY small amount.

[Static]

I don't have any other ideas for you except maybe wearing rubber gloves when you have open cuts and need to put your hands in your tank. Electricity or not it's probably a good idea.....

good luck

myles