Stray Voltage

smd189 · Feb 27, 2021

I noticed my tang is showing signs of HLLE. I did run carbon almost constant until 2 weeks ago when I noticed the tang. Water parameters are ppretty good. (0 nitrate, 0 phosphate, 8.3 ph, calcium 450, alk 10).
I checked for stray voltage and found .30 on my meter when set like in picture. I just dont know exactly bow to read this or if I have it set correctly. No matter what I turn off in the tank it still reads .30. Will all aquariums read a certain level of stray voltage? Where does .30 stand compared to the norm. Any help would be greatly appreciated. Thank you.

theMeat · Feb 27, 2021

Plug tank into gfci protected outlet, and instal an aquarium ground probe. These two things work together to keep you and livestock safe

zalick · Feb 27, 2021

smd189 said:
I noticed my tang is showing signs of HLLE. I did run carbon almost constant until 2 weeks ago when I noticed the tang. Water parameters are ppretty good. (0 nitrate, 0 phosphate, 8.3 ph, calcium 450, alk 10).
I checked for stray voltage and found .30 on my meter when set like in picture. I just dont know exactly bow to read this or if I have it set correctly. No matter what I turn off in the tank it still reads .30. Will all aquariums read a certain level of stray voltage? Where does .30 stand compared to the norm. Any help would be greatly appreciated. Thank you.

It's likely induced voltage aka phantom. If you have an analog multimeter, use that instead and it will read 0.

smd189 · Feb 27, 2021

theMeat said:
Plug tank into gfci protected outlet, and instal an aquarium ground probe. These two things work together to keep you and livestock safe

I am plugged into. GCFI. I can get a probe. Thank you.

smd189 · Feb 27, 2021

zalick said:
It's likely induced voltage aka phantom. If you have an analog multimeter, use that instead and it will read 0.

I don't have an analog meter but can order one. Is their one you recommend? What setting do you set it in? Thanks.

zalick · Feb 27, 2021

smd189 said:
I don't have an analog meter but can order one. Is their one you recommend? What setting do you set it in? Thanks.

The cheapest one they have at home depot. Good to have on hand in general. Just set it to 120 ac and it won't detect induced voltage.

theMeat · Feb 27, 2021

smd189 said:
I don't have an analog meter but can order one. Is their one you recommend? What setting do you set it in? Thanks.

If you put a ground probe in you don’t need a meter. Any stray voltage and gfci trips. Then you unplug one thing at a time til you find the culprit

Greg P · Feb 27, 2021

From your picture, you have the meter set to DC voltage.
Set it on the right side to AC 200 (just to the right of 600)

Greg P · Feb 27, 2021

AC voltage is represented by this symbol V~

smd189 · Feb 27, 2021

Greg P said:
From your picture, you have the meter set to DC voltage.
Set it on the right side to AC 200 (just to the right of 600)

If I set it here, it shows 0.00. Is this correct? Thanks.

Greg P · Feb 27, 2021

If you have the black lead in the ground port of an outlet and the red lead in the water then yes you're good to go.
While you are at it, dry the probes/leads and place the black in the ground port and the red in the top right socket -the shorter of the 2 vertical ones if your outlet is polarized. If you get up to 120 volts you know your outlet is grounded and your water test was successful.

smd189 · Feb 27, 2021

Thanks so much. I just performed your test, and yes it shows 119-120. Did the tank again and 0.00. So I guess I can role out that cause. Must be GAC. He eats great and gets nori daily. Any idea how long after GAC is removed to expect improvements? Thanks again.

Greg P · Feb 27, 2021

Personally can't remember how long it took but my YT did recover. I was able to stop using GAC in early 2016 with no ill effects to my SPS

ca1ore · Feb 27, 2021

Bah humbug, stray voltage = red herring. HLLE is much more likely to be diet.

CMMorgan · Feb 27, 2021

I had stray voltage - zap zap zap zap. I added a ground probe and life is good.

Greg P · Mar 4, 2021

CMMorgan said:
I had stray voltage - zap zap zap zap. I added a ground probe and life is good.

ca1ore said:
Bah humbug, stray voltage = red herring. HLLE is much more likely to be die

Regardless of what is causing HLLE for your Tang ...
Stray voltage is still a health issue for YOU.
Thankfully you don't have any, so your tank is safe for you to work in.

Just adding a ground probe without knowing what voltage you have in your water is not advised. You should always have a GFCI if you add a ground probe. I grow tired of posting this info. Search the web about it ... a probe with no GFCI can stop your heart.

Stray voltage is not the biggest contributor to HLLE. Use of GAC in a reef comes in second, but only if it's powder is allowed to enter the tank.
Diet is the biggest issue, with GAC coming in second. And many will argue this.

I had the best success healing my Yellow Tang's HLLE issue by removing GAC use.
I had no stray voltage issues before, during or after.

Greg P · Mar 4, 2021

STOP telling people to install ground probes without GFCI outlets !!!!!!

Greg P · Mar 4, 2021

I don't know if there's a sticky or other thread about it ... I wish I could find one to point everyone to

GROUND PROBES

A grounding probe is a piece of metal (silver or titanium, to be reef safe) that connects the system’s water to the home’s electrical grounding conductor. Grounding probes are somewhat controversial in the hobby. The probe adds a degree of protection against electrical shock but at the same time may allow current to flow through the aquarium and its inhabitants. The following examples will help to illustrate the concepts presented here. When a person comes in contact with the water AND the ground

Example #1: A powerhead in the tank develops a hole in the insulation of the HOT wire. The powerhead is not plugged into a GFCI and there is no grounding probe. Because there is no path for current to flow, the powerhead operates normally. Nothing in the aquarium is exposed to current flow. When a person comes in contact with the water AND the ground, then current will start to flow through that person. Because there is no GFCI to sense the imbalance, the person will receive a serious electrical shock and possibly be electrocuted! It should be very clear that a GFCI is a MUST HAVE piece of safety equipment!

Example #2: A powerhead in the tank develops a hole in the insulation of the HOT wire. The powerhead is not plugged into a GFCI and there is a ground probe. Because there is a path for current to flow, the inhabitants of the tank are exposed to electric current. Furthermore, when a person comes in contact with the water AND the ground, then current will start to flow through that person. Because there is no GFCI to sense the imbalance, the person will receive a serious electrical shock and possibly be electrocuted! It should be very clear that a grounding probe used WITHOUT a GFCI is very dangerous proposition.

Example #3: A powerhead in the tank develops a hole in the insulation of the HOT wire. The powerhead is plugged into a GFCI but there is no grounding probe. Because there is no path for the current to take, no current flows and the pump operates normally. Nothing in the aquarium is exposed to current flow. When a person comes in contact with the water AND the ground, then current will start flow through that person. The GFCI will sense the leak and trip, preventing serious electric shock.

Example #4: A powerhead in the tank develops a hole in the insulation of the HOT wire. The powerhead is plugged into a GFCI and there IS a grounding probe. As soon as the HOT wire is exposed, current will begin to flow through the tank water to the grounding probe. The GFCI will register this leak and trip.

There are plenty of other scenarios to look at. What happens when both the HOT and NEUTRAL (or ground) of a piece of equipment are both exposed underwater? With or without a GFCI, current will flow locally from the HOT to the NEUTRAL (or ground). The GFCI (if in place) will NOT trip because there is no current imbalance. The tanks inhabitants will not likely be aware of the current flow either. Placing a hand in the tank could provide a nasty shock! A grounding probe in conjunction with a GFCI would prevent this by causing the current to flow to the probe, and thus tripping the GFCI. The same holds true if two different pieces of equipment develop small leaks, one HOT and the other Neutral. The probe and GFCI combination would allow current to flow to the probe, subsequently causing the GFCI to trip.

Using a ground probe without GFCI protection on all of the submerged (or exposed) equipment creates a dangerous situation for the tank’s inhabitants and humans exposed to that tank. A ground probe must always be used with GFCI protection!

smd189 · Mar 4, 2021

Greg P said:
Regardless of what is causing HLLE for your Tang ...
Stray voltage is still a health issue for YOU.
Thankfully you don't have any, so your tank is safe for you to work in.

Just adding a ground probe without knowing what voltage you have in your water is not advised. You should always have a GFCI if you add a ground probe. I grow tired of posting this info. Search the web about it ... a probe with no GFCI can stop your heart.

Stray voltage is not the biggest contributor to HLLE. Use of GAC in a reef comes in second, but only if it's powder is allowed to enter the tank.
Diet is the biggest issue, with GAC coming in second. And many will argue this.

I had the best success healing my Yellow Tang's HLLE issue by removing GAC use.
I had no stray voltage issues before, during or after.

Thank you. Great info. Once I read about hlle, I immediately thought GAC was most likely my issue. Being new, I assumed there was no down side to using it all the time. I would rinse it, but not that well. I was also using cheap carbon.

My tang eats well and I try to keep nutrition as good as possible.

I pulled the GAC out about 10-14 days ago when I noticed the hlle. The bad thing is that looking back over pictures, he had it for sometime. Good news, doesn’t appear to have gotten worse.

My question is assuming the GAC caused this, how long should I expect it to take to start improving? I realize some scarring will be permanent.

Thank you again for the help.