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Would stray current kill a fish? (1 Viewer)

Blownsvt

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I just got a call from my wife telling me that she found my yellow eye kole tang dead in my tank. She says whe she puts her arm in the tank she can feel it get tingly/numb which I am assuming would indicate some stray current in the tank. I have had this fish for 2+ years and suddenly it is dead today. Would electric current cause something like this? I just had her pull the heater out thinking it would be the cause and she says that she is not getting shocked anymore now that it is out.

Pissed at a fish being killed....... :mad_3:
 
I run a grounding probe on every tank after I lost a fish in my first tank to a bad wire on a cheap powerhead.
 
ground probe is designed to take stray current from an aquarium, pond, or standing water source and discharge it onto your home ground the way your electrical devices 'should' had they been built with a grounding structure in them (3 prong plugs).

you can purchase grounding probes from various resources including online fish hobby and pond supply retailers as well as local fish stores, and local pond supply stores like Bachmans and Home Depot when the pond section reopens.
 
First off I am not an electrical engineer but it is my understanding that you can not get shocked unless you are grounded. The idea behind a grounding probe is that it (hopefully) gives any stray electricity a better ground than going through your body to ground. It does't stop a current from running through the tank full of salt water, it in fact helps it.

What you really need is a ground fault interrupter GFI. It will turn off the power if it senses stray current.

The only times I have ever noticed stray current was while standing bare footed on the concrete floor or when I touched the metal parts of a grounded light fixture while my other hand was in the water.

To test you can use a basic multi tester set at the std house voltage range. Put the pos (red) probe in the tank water and touch a known ground with the neg (black) probe ( I carefully use the ground of and electrical outlet). If there is voltage present you will get a reading above zero. Usually its only a small amount of voltage leaking or the circuit breaker would have already tripped.
 
First off I am not an electrical engineer but it is my understanding that you can not get shocked unless you are grounded. The idea behind a grounding probe is that it (hopefully) gives any stray electricity a better ground than going through your body to ground. It does't stop a current from running through the tank full of salt water, it in fact helps it.

What you really need is a ground fault interrupter GFI. It will turn off the power if it senses stray current.

correct, you will not get shocked unless you yourself are grounded, electric current follows a path to ground, if it cant get to ground through you it wont go through you.

the ground probe would essentially turn the water into a conductor in the circuit, i could see more issues with livestock getting harmed from shorted electric current when a ground probe is in use rather than one not in use. As the voltage potential is no longer sitting around waiting for a path to ground, it has a path to ground and will run from the shorted device to the ground probe and then to ground continuously until the short was repaired or probe removed.

a GFCI will not trip or prevent stray current from entering an aquarium, you can still get shocked from faulty equipment granted you yourself are grounded. Now if you use a ground probe, you will actually end up triggering your GFCI as the current on the ground would trip it.

Personally i wouldnt use a ground probe, there is no way for your fish to get shocked by stray current in the aquarium. Unless the fish is tall enough to touch the floor while still touching the water (if its a basement floor with concrete base) or if the fish manages to touch a ground wire on your lighting system while still touching the water in the tank (this would also require your power cable to be frayed and ground wire bare and exposed).

The ground probe will trip the circuit and end up shutting down your tank, wouldnt be so ideal if this happened while you were at work or away at the lake house or something. In my personal and professional opinion, if you have a short, correct it, dont use a ground probe.
 
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I had a yellow tang a long time ago (in another tank) and it developed a hole in its head. People I spoke to about it said it could have been due to stray voltage in the tank, and to install a ground probe. I picked up a chunk of titanium from work (or you could use a titanium tent stake from REI), connected a copper wire to it (the copper was outside the tank) and connected it to the ground plug on an old modified outlet plug. This completely stopped the damage to my tang.

This time around, I went the easy route and just picked up a $9 ground probe, which does the exact same thing. It plugs into a regular outlet, but has plastic plugs for the two main prongs. The ground prong is metal and connects to a titanium rod that sits in my tank.
 
a GFCI will not trip or prevent stray current from entering an aquarium, you can still get shocked from faulty equipment granted you yourself are grounded.

But the GFCI would trip if you stuck your hand in the tank and you were grounded. Probably feel it but it shouldn't kill you. That's a good thing.

Like I said, I have had power heads and heaters fail but I think the highest stray voltage I have measured is 8V (but you can still feel it).

PS: I spent hours once trying to figure out what was shocking me. Every time I stuck my hand in the tank I felt a tingle. I tested and unplugged everything and couldn't find the short. It turned out I had a metal sliver in my hand and the salt water was making it work like a battery. Duhhhh. I never touch the water in my basement sump without shoes on anymore. Just too good of a ground standing bare foot on the concrete.
 

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