Stray Voltage

mike31154 · #1 03-10-2014, 05:40 AM

Voltage measured with a meter from a tank to ground is not necessarily an issue. It's when the voltage has a path to ground. This will result in current flow from the voltage source to ground. If something of lower resistance gets between the voltage & ground, that results in shock. Generally, if the electrics running your tank are plugged into a GFCI outlet, you'll be safe. While 30 volts is getting up there, there are many pitfalls when trying to measure voltage & current in salt water. If you're not getting zapped when touching the water & the livestock isn't acting weird, there shouldn't be cause for concern.

Seriak · #2 03-10-2014, 04:10 PM

Thanks all. I am using a digital multimeter from the ground of an outlet to the tank.

Ron99 · #3 03-10-2014, 10:13 PM

My experience is that stray voltage is not good. I had a problem years ago with it. It wasn't enough to give me a shock but I noticed it when a cut on my finger was "buzzing" like putting a 9 volt battery on your tongue. I didn't measure the magnitude of the voltage but guessing it was under 20 volts. That was enough to cause slow death of corals and fish over several months. So I would be worried about it.

Simons · #4 03-11-2014, 03:10 AM

to be honest, I never really thought about it but, with all of the equipment in a small space the possibility is always there.

I installed a $9 grounding probe I picked up in a recent order from J & L. I just grounded my sump, not the display tank since it's just a holder of the water and nothing is submerged on the DT.

Seriak · #5 03-11-2014, 01:27 PM

Quote:

Originally Posted by Simons

to be honest, I never really thought about it but, with all of the equipment in a small space the possibility is always there.

I installed a $9 grounding probe I picked up in a recent order from J & L. I just grounded my sump, not the display tank since it's just a holder of the water and nothing is submerged on the DT.

I will not add a grounding probe to my tank. I value my fish over myself

mike31154 · #6 03-11-2014, 02:20 PM

There's an abundance of info out there on the subject of grounding probes/stray voltage. Bottom line is, protect yourself by ensuring any electrical equipment associated with your tank is on a GFI protected circuit and if you have any doubt about a piece of equipment, even if it's relatively new, replace it. I value me, family & friends over my fishies.

reefermadness · #7 03-11-2014, 07:24 PM

GFCI should be manditory piece of equipment. A grounding probe in conjunction with a GFCI is a good idea for added safety.

40volts is a lot. Some small voltage is expected and can simply be induced by properly working equipment being submerged in water. But seeing voltage at 12v or higher I would be very concerned myself as that is going to be a good sign that a piece of equipment is open or shorting. Some of our powerheads work on these 12v-24v low levels of DC voltage but that amperage on short can definitely lead to livestock problems.