Help. I just got shocked by the water.

That's what makes me want to go reread those articles alleging grounding rods make matters worse... I still use one.

 

I was thinking about the same thing regarding the grounding probes... If they aren't affected since they aren't grounded, and when they are grounded they get zapped, then how does this a good thing?

Anyone?

 

I can feel a slight tingling sensation if I put my finger in the tank and my arm touches the metal housing of my light fixture. There is always some amount of conduction from your pumps, heaters, etc... because nothing is a perfect insulator. You will have some measurable voltage induced in the tank. But it sounds like you have a completely different situation since you are getting zapped just standing on your floor. You need to figure out what the deal is ASAP. Sounds like you have an intermittent connection or a frayed cord someplace in your tank.

The other possibility is salt creep. It's possible that you had some salt creep down a cord to a power strip. If the salt is kept moist it will be highly conductive. If it was salt creep the process of unplugging and plugging could have knocked off and caused the problem to go away. If you can't find the problem just don't assume this was the case and forget about it.

A grounding probe will set the water in your tank at the same ground potential of your house ground. It will not eliminate the source of your current which is what you are feeling when you stick your finger in the water. If you add the ground probe you won't feel it anymore because the current is traveling over the path of least resistance and picking the ground probe instead of you. If you have an electrical issue then adding the ground probe will actually cause more current to flow through your tank and it will be there all the time. I would think that would be a problem for your fish but your first priority right now is your own personal safety. I recommend the ground probe for your protection until you have this figured out. Do not rely on your GFI circuit since it sounds like it is not wired properly anyway. You need to get that outlet fixed first.

We could debate all day about the virtue of ground probes for tanks. It sounds like you have a safety issue that goes way beyond that. You need to get that outlet grounded ASAP. The ground probe won't do anything if it is connected to an ungrounded outlet anyway.

 

[/quote]We could debate all day about the virtue of ground probes for tanks. It sounds like you have a safety issue that goes way beyond that. You need to get that outlet grounded ASAP. The ground probe won't do anything if it is connected to an ungrounded outlet anyway.[/quote]

+1 on that - you need to get a true ground installed asap. to many stories are out there about injuries and house fires from poorly set up salt tanks. I did my undergrad research in marine biology, and worked in a large basement marine aquarium set-up. i can't tell you how many times i got warning shocks as i was about to do something stupid. imagine if a short starts up at home and no-one's around...

for what sounds like very old electrical service at your place, you probably should just get an electrician in and put in dedicated service for your tank or the room your tank is in. there are ways to 'jerry-rig' a ground inside a single electrical socket box that -usually- will provide a true ground.

btw, your gcfi isn't working. if it was, and there was a short connection between your lights and you tank (the one that shocked you), your gcfi would have tripped - either when the short developed, or at least when you touched the tank and closed the circuit to ground. gcfi are only as good as the installer and installation.

good luck, and be safe.

 

A few myths here. First, a GFCI doesn't need a ground to do what it does. It opens the circuit if there exists an excess of 4 to 6 mA of current between the hot and the neutral.

Next, a ground probe will accomplish nothing if your premises wiring is not grounded; as it only serves to be a route directly to ground for the tank water.

For salt creep to migrate down an electrical cord to the receptacle; the cord would have to be badly neglected for years and years, and you would be able to see dried salt crystals covering the entire cord. It's almost a sure bet this isn't the culprit.

Finally, static electricity manifests itself just like a lightning strike, as your body is used to dissipate a difference in electrical potential. It happens instantly, is short lived, and would take minutes of similar activity to happen again. Like the original poster said, it would not be a sustained event.

It would be a good thing to have your premises wiring grounded, but once the ground rod is driven and the panel is party to the connection, every receptacle in the residence would have to be rewired to accomodate a 3 wire system. This is bound to be a tremendous expenditure, because most homes are not wired with conduit, so new wire often can't just be pulled to each wall outlet.

To address the original question--what would cause this and if it makes any sense--I'd be curious to know one thing: After you unplugged everything, and plugged back in the lights, and the problem was gone, was everything else which was previously unplugged up to that moment plugged back in?

Your circuit breaker is bound to be old, and you describe a panel where much of the house is on one breaker. You might consider having that breaker replaced. That would be a reasonable, relatively low-cost first intervention. With some luck, it might solve the issue.

Good luck!

 

I woke up this morning and stuck my finger in the tank just to see what would happen and was shocked AGAIN.

Reefsparky: Thank you for the explanation on the GFCI not NEEDING to be grounded to work to some degree. I do agree that it should be grounded however it's not at the moment and that's how it is.

About salt creep and the cord, my lfs owner said that you don't necessarily have to have old and neglected cords, it can do it if you can't even see the salt with your eyes. It has also been suggested to me by tangster actually that since my lights sit on my tank that I could have salt creep on the bulbs, then salt creep on the tank rim which may be going to the water. I am going to clean everything and try again.

I have been thinking about having these outlets re-wired. While installing a GFCI in my kitchen last week I found that in that part of my house I do have 3 wire true grounds. This means the whole house does not need to be done. As far as my panel in the basement goes, it's new, it was newly installed when I bought my house 10yrs ago.

About the unplugging and plugging stuff back in, I plugged everything back in exactly how it was and everything was fine. This morning after I got zapped again I just unplugged my lights and it's ok now. Going to give the lights and tank rim a cleaning and see what happens!