118+ volts in my tank?

[Chads29]

For over a month now I have been having issues with some of my sps.

I had really concluded that lighting was my main culprit on top of a few other things i did while trying to "Fix" the problem.

I have had a few colonies rtn about half there tissue over the course.

I immediately pulled whatever one was rtn'ing when I came upon them and put them in another tank where they miraculously stopped rtning. Nearly all of the affected colonies are still alive and recovering.

Having witnessed this I figured that it must be something in my system. So I have done many many water changes. And a few other things.

Overall the corals in the system with the problem seem to be slowly recovering I lost another acro yesterday that was quite a surprise because It really seemed like I had rounded a corner on this whole thing.

Here is where it gets a little interesting.


I had run a tether float switch in my sump as a safety measure for about three years.

Well last wednesday I was changing a filter sock in the AM with out my shoes on and I tripped the switch. When I went to flip it back up I got a good shock and my gfi then tripped.

I immediately removed it from my system.

I went out and got a multimeter out of curiosity and this is what I discovered.



So I am not sure if the float switch was leaking 118 volts into the water this whole time but I found a thread that talked about voltage in saltwater forming chlorine and I had to wonder if this has been my problem. Or part of it.

Sorry for the loooong story but any input on this one would be greatly appreciated.

[tkeracer619]

Yikes.

I use autotopoff.com dual floats with the low voltage option. Worked great for many years. Just purchased another set for my second tank. Same great quality components.

[Lorenz725]

WOW well first off I am glad you are ok there has been way to many stories about people getting shocked in there tank lately. Hope it opens peoples eyes about making sure they use GFI outlets for there tank. I hope everything recovers and you found the problem. Good luck

[dma]

Put a ground probe into the tank. That way any stray voltage will trip the GFCI.
It is important to remember that when the GFCI trips, it will no longer supply power to the electrical devices connected to it. The good thing about this configuration is that it facilitates immediate recognition of a ground fault. The bad thing is that it will cause the devices normally supplied with electrical power through the GFCI to stop working, possibly compromising the well-being of your tank's inhabitants.
My advice is to lose the float switch. This is a line-voltage device intended for the control of sump pumps, not marine aquaria.

[alton]

dma is right on, the only thing I would add is keep your return pump on its own GFCI so not to stop when something else goes bad.

[Jeff000]

Originally Posted by dma

Put a ground probe into the tank. That way any stray voltage will trip the GFCI.
It is important to remember that when the GFCI trips, it will no longer supply power to the electrical devices connected to it. The good thing about this configuration is that it facilitates immediate recognition of a ground fault. The bad thing is that it will cause the devices normally supplied with electrical power through the GFCI to stop working, possibly compromising the well-being of your tank's inhabitants.
My advice is to lose the float switch. This is a line-voltage device intended for the control of sump pumps, not marine aquaria.

NO!

A ground probe means there is current and not just voltage. Current is bad.
Ground probes are NOT the answer, fix your faulty equipment.

There will almost always be some voltage in the tank, but you have to remember that to measure it you are measuring between two different potentials, so your reading means nothing. The movement of the salt water induces a voltage, just like in the ocean. Some lighting will induce a voltage into the tank too, florescent most notably. Again this voltage is nothing to worry about, but if you put a ground probe in you are letting that voltage get to ground creating current. You can think of this as a bird on a power wire.... until you put a ladder up on that wire to get the bird....

[ErikS]

Points out a good philosphy - avoid as many 120v devices in the tank as possible. We've got pumps & powerheads running 12-18v...........hopefully eventually we'll have everything running like that. (well okay, heaters are going to be tougher )