Stray Tank Voltage

[AaronS]

Good evening all.
Many times over the decade I have had this tank, Ive had pumps or heaters give me a taste of their voltage.
Usually I unplug things until I don't get zapped but I refuse to play that game with the amount of electronics attached to the tank.

I *believe* I correctly set the VOM to the correct AC setting, ground wire to center screw on GFCI. Red wire+ from the VOM hanging in the tank.
I had I believe 76v taking an adventure throughs the tank, it tested the same whether I checked the sump or DT.
I played the game unplugging electronics. I found a sump power head that when unplugged, the VOM read 002 instead of 076.
Is that correct? My question being A. did I truly narrow it down or should it read 000. B. did I actually use my VOM correctly. My VOM gets most of its usage on 12v of car voltage not AC house voltage.

I do keep a grounding rod in the sump, I removed it for this test.
The tank has been going for about a decade, some of the pumps etc. are original. I have swapped many of them out, but I like to check and confirm my work. I once had a brand new UV bulb leak voltage, fresh out of the box.

 

[Jack Landers]

.Set your volt meter on the lower setting (200 volts) and unless your meter is calibrated, it may be a slightly high reading showing 2 volts. Looks like you found the culprit. If in doubt, stick your finger in and see if it gets you.

 

[project1004]

Particular power heads are known to cause issues with stray voltage. No longer in business. Was it Koraria? I had this happen when I first started the reefing hobby.

 

[enderg60]

Unplug everything and then plug things in one by one to see whats causing it. Whatever it is, replace it.

I doubt stray voltage in the tank is a bad thing. Ive had equipment fry and shock the crap out of me when I put my hand in the tank but nothing in the tank seemed to care.

I tried grounding probes way back when but not I dont bother. Im going with the thinking that unless there is a ground present the "stray voltage" can not complete a circuit.