Shock when touching water surface

[Genj]

Every now and then I'm getting a mild shock while touching the surface of my tank. I've got a ground probe hooked up and in the water.

 

I've got a digital meter, should I just place the probes in the water on the voltage setting, or test using some other mode?

 

I'm concerned that the stealth heater may be leaking voltage into the tank. I switched over to this heater when I changed tank, as I didn't trust the Theo heater.

[JPF]

Winter static buildup? You could pour fabric softener in the tank to reduce this. Not sure if fabric softener is reef safe. Better ask over at RC.

[Genj]

Yeah, I was thinking that and I put the downy bear into the water... it didn't help.

[senoufo]

do you have carpet around your tank ( i'll spare you to answer if you have shag carpeting in the tank ;-)

[Genj]

yes, I figured it was static buildup from walking around in socks, and touching the water surface is the same as touching a light switch. Since the tank is an extension of the ground in the house I figured it would do this. I just wanted to post and double check to make certain.

[senoufo]

ok your cool, you just have a magnetic personality.

[jestep]

I would bet the ground probe is enabling you to shock yourself on the water via static. Without a ground probe, the water wont be grounded so you wouldn't get shocked.

 

For testing, just put your meter on AC Voltage and test from the water to the ground hole in an outlet (round one), or directly to your grounding prove.

 

Also, the grounding probe cannot be in the water if you are testing for stray voltage or a direct short. When it's in the water any current will go through the probe instead of your meter. You'll get a false reading at best, but most likely no reading when the probe is in there.

[zemuss]

It could be a pump, skimmer pump or a heater shorting. About a month or two ago I had the same issue and it was a pump shorting.

"Z"

[nibor]

It is static. If it was a piece of equipment leaking enough current to shock you and you've got a grounding probe, you would expect your GFCI to trip continually or at the very least all your live stock would be looking sad/dead as they would be continually exposed to the same shock that you are feeling.

[zemuss]

In my case it depended where the pump was. Since I have a sump the shock seemed to stay by the return which caused RTN of my SPS. It also caused my clowns to stay lower in my tank. YOu might not agree but it didn't affect the whole tank.

[nibor]

Pumps are the usual culprit in cases such as yours Zemuss. Do/did you have a ground probe?

[Genj]

Thanks for the testing instructions jestep!

[NU2REEFIN]

I have noticed with my tank 29g Biocube HQi, that if i am standing on the concrete floor next to my tank rather than the rug by my tank and touch the water I feel a little shock. I just figure it is due to ballast sitting on the floor. There is no shock at all if I am on the rug, and there is no sign of the corals and fish being harmed.

[Scottynose]

I've got a ground probe hooked up and in the water.

[cptbjorn]

i don't really understand the point of ground probes, it seems to me that if you have a voltage potential coming from one of your pumps/heaters then the solution is to replace it. putting a ground probe in the water just causes current to flow and my guess is it makes the problem worse at least as often as it makes it better...

[nibor]

Agreed. From your live stock's perpective they make the problem worse, never better. They are for our safety not the well being of our pets. Saying that a ground probe has fixed a stray voltage problem is like saying that all the hair algae has fixed your high nitrates. There are some situations when a grounding probe should be used however, for example an aquarium containing sharks which are very sensitive to electromagnetic fields. Of course in this case equipment should be regularly tested to make sure that it is not "leaking" and current is not flowing in the aquarium.

 

jestep's got it about right and I agree with his opinion of the OP's shocks.

 

@Scottynose. If that quote was directed at me, my question was for zemuss not the OP.

 

@NU2REEFIN. That's because when you are standing on the rug you are insulated from ground.

[jestep]

Also agreed on the grounding probe issue. I can't see how it can be better for anything, except humans, if there is a probe in there. Unless there are 2 voltage sources in the tank, there shouldn't be any current flow. With the grounding probe, there is guaranteed current flow in the tank.

 

I don't want to dispute others' corals with RTN or other apparent electrical related death, but the probe to me seems like it would make matters much worse.

 

@NU2REEFIN

 

It may be a good idea to test the tank just in case you have a serious short in the tank. In my FW tank, I could feel a very slight tingle for over a year, but no problems. I upgraded my light fixture to a metal tek fixture which was grounded. Next time I was cleaning my tank, I got a full 120 with my arm at the bottom of the tank. It's pretty amazing how much carpet or shoes insulate a person from an electrical current. I would test just to be on the safe side.

[zemuss]

No ground probe in my tank currently.

[nibor]

I'd guessed. A pump with enough insulation damage to shock you would have caused a relatively high current to flow in the tank continually IF you had a ground probe. The fact that you do not have a ground probe prevented your livestock from being shocked but not you. When you placed your hand near the pump, you provided a path for the current to flow to ground.