Aquarium and electrical safety

[Idech]

Oh I didn’t know about @Miami Reef. This is so sad.

It’s hard to understand too because he seemed like a careful and knowledgeable reefer. RIP @Miami Reef. We will miss you.

 

[BeanAnimal]

Other things to consider though much debate on though is grounding rods installed in your tank. A titanium heater with a 3 prong outlet can double as a grounding rod.

A ground probe should NEVER be used unless the entire system is GFCI protected. The probe increases personal danger if full GFCI protection is not used. It enhances safety only if used with full GFCI protection.

I would also caution folks that a GFCI is not foolproof.

I’ve gotten some small shocks off of plugs in a GFCI outlet when handling wet plugs. Big no no.

If all of the electricity coming out of the GFCI outlet goes back into it through the other side of the outlet, it won’t trip, even if it passes through you in the meanwhile.

Correct. For example, if you are wearing insulated shoes and grab the hot and neutral conductor of a GFCI protected circuit, you will get shocked. There is no fault path, you are the load, no different than a lightbulb or a motor.

 

[BeanAnimal]

Ouch!

My father tried to explain it to me (to no avail) - that with both hands in the water, there is electrical potential across both hands and current flowed through my chest. If I had just put one hand in the water, he said I would have been o.k. In your case, the current flow would have been from one hand to your mouth.

It depends on the potential between hands, etc.

It is never a bad idea (and is a general rule) to leave one hand behind the back when working in a potential shock hazard.

Likewise be careful of having a hand in the tank and an ear, neck or other arm being grounded (say touching a light fixture).

 

[jonelder68]

Ouch!

My father tried to explain it to me (to no avail) - that with both hands in the water, there is electrical potential across both hands and current flowed through my chest. If I had just put one hand in the water, he said I would have been o.k. In your case, the current flow would have been from one hand to your mouth.

Yep both hands completed the circuit/path for electricity.

We use to play a dumb game in high school auto shop class. Would charge a capacitor and form a human chain by holding hands. Then the unsuspecting person would be at the end of the chain and would receive the shock/jolt as he was the end of the circuit and connected to ground. Electricity is very interesting to say the least.

 

[JonoH]

Thankfully here in Aus our regulations mean that every power circuit is on an RCD safety switch.

I also use Safety Switch boards as an extra bonus - the one that always catches me though is the water change station.
Pumps getting moved in and out of tanks and drums, the cables get weak around the connection points and start to break.

 

[jonelder68]

A ground probe should NEVER be used unless the entire system is GFCI protected. The probe increases personal danger if full GFCI protection is not used. It enhances safety only if used with full GFCI protection.

Agree! But our tanks should never be operational without a GFCI installed is what I’m preaching

 

[BeanAnimal]

The intention is to write a sticky post for the forum, but it needs to be done correctly and clearly and concisely. That will take some time.

In general people should be using full GFCI protection and not doing any electrical work unless they are fully qualified.

Miami did hire a professional when he had problems a few months back and I urge people not to speculate about what happened.

Even when everything is wired properly, there are still hazards to understand and rules to follow.

 

[Damage12]

Is it correct to say that having the tank equipment on GFCI’s plus those outlets are connected to an arc protection circuit breaker is the best case scenario?

 

[Jay Hemdal Verified Community Expert]

Yep both hands completed the circuit/path for electricity.

We use to play a dumb game in high school auto shop class. Would charge a capacitor and form a human chain by holding hands. Then the unsuspecting person would be at the end of the chain and would receive the shock/jolt as he was the end of the circuit and connected to ground. Electricity is very interesting to say the least.

My father also warned me about working on old tube TV's and showed me how to short out the capacitor before doing any work inside.

 

[Jay Hemdal Verified Community Expert]

It depends on the potential between hands, etc.

It is never a bad idea (and is a general rule) to leave one hand behind the back when working in a potential shock hazard.

Likewise be careful of having a hand in the tank and an ear, neck or other arm being grounded (say touching a light fixture).

Yes - I've seen the difference that distance can make with electrical potential; with electric eels, small fish can swim right up to them with impunity, while a larger fish, intersecting more of the DC current, will be shocked in the water, even when there is no path to ground.

 

[jonelder68]

Is it correct to say that having the tank equipment on GFCI’s plus those outlets are connected to an arc protection circuit breaker is the best case scenario?

You usually do one or the other. I personally prefer the breakers in the panel over wall outlets. I’ve had wall outlets fail to trip or false trip and wouldn’t reset until replacing. It’s also why if you are using outlet gfci’s i recommend testing them with a tester at least annually. But GFCI breakers can be tested as well with the tester tool.

 

[exnisstech]

I've been calling "stray voltage" "induced voltage" now - what I mean is a small voltage, usually less than 30 vac that is produced by the normal operation of electrical motors in the tank. That doesn't harm the fish, and I've never felt that "tingle" working around tanks that had it. A "short to ground" may not be the best term for the dangerous situation that can harm people and fish, but that stems from some failure of the equipment - a short, or electricity following salt incrustations on a power cord, etx.

Apologies Jay, I've been using the wrong terminology.
Do you know how much voltage is needed before tank inhabitants are affected?
Asking because I had 50 volts once and there were no signs in the tank but I sure felt it. Like you I was standing on chair. It would have made for an entertaining video.
The 50 volts came from leaking powerheads so that would be stray voltage.
I remember Paul B once saying that there will always be some voltage in the tank so that would be induced voltage. I get it now

 

[Jay Hemdal Verified Community Expert]

Apologies Jay, I've been using the wrong terminology.
Do you know how much voltage is needed before tank inhabitants are affected?
Asking because I had 50 volts once and there were no signs in the tank but I sure felt it. Like you I was standing on chair. It would have made for an entertaining video.
The 50 volts came from leaking powerheads so that would be stray voltage.
I remember Paul B once saying that there will always be some voltage in the tank so that would be induced voltage. I get it now

Sorry - I don't know the exact human threshold for feeling induced current. Last week, I got a "tingle" from my electric golf cart running at 48v DC, but it was so minor, I wondered if I just imagined it.

 

[BeanAnimal]

You usually do one or the other. I personally prefer the breakers in the panel over wall outlets. I’ve had wall outlets fail to trip or false trip and wouldn’t reset until replacing. It’s also why if you are using outlet gfci’s i recommend testing them with a tester at least annually.

Code now requires one or the other (AFCI or GFCI) depending on circuit designation and service location for most circuits (beyond the scope of this conversation). The scope expands with each code revision.

AFCI breakers can be problematic with motor, ballast and some switch mode power supply loads. Sadly, they are also ideal for things like arcing in a power strip caused by salt creep. So, a dilemma for aquarium owners.

If you want Arc Fault protection, then either a combo AFCI/GFCI breaker can be used or an AFCI breaker with GFCI receptacles.

While nuisance trips can be catastrophic for the tank, they added protection with regard to personal safety may be worth the risk.

 

[BeanAnimal]

Sorry - I don't know the exact human threshold for feeling induced current. Last week, I got a "tingle" from my electric golf cart running at 48v DC, but it was so minor, I wondered if I just imagined it.

~6 mA for DC and less for AC (~1.5 mA)

This of course depends on where it touches you and the resistance of your skin. You may not feel 5 mA on the fingers, but get a good tingle if it were to touch the forearm. Likewise cuts or open sores have far less electrical resistance and you may feel the shock more readily on those spots on a submerge hand for example.

 

[revhtree Verified Admin]

Code now requires one or the other (AFCI or GFCI) depending on circuit designation and service location for most circuits (beyond the scope of this conversation). The scope expands with each code revision.

AFCI breakers can be problematic with motor, ballast and some switch mode power supply loads. Sadly, they are also ideal for things like arcing in a power strip caused by salt creep. So, a dilemma for aquarium owners.

If you want Arc Fault protection, then either a combo AFCI/GFCI breaker can be used or an AFCI breaker with GFCI receptacles.

While nuisance trips can be catastrophic for the tank, they added protection with regard to personal safety may be worth the risk.

What method do you suggest for full protection of the human operating the tank? Tank inhabitants aside.

 

[Damage12]

Thank you both for the explanation. Just planning this out for my upcoming build. I’ve had an arcing power strip that was wall mounted and the one time in 15 years where the fish splashed in the perfect area and saltwater got into the power strip. Scary and I’m glad I was home to catch it.

 

[JGT]

They also make combo AFCI/GFCI outlets that can be used. Only the first one needs to be an AFCI/GFCI outlet in a series. The rest can be regular outlets connected to its load terminals and all outlets are protected.

 

[UncommonSense]

AFCI breakers can be problematic with motor, ballast and some switch mode power supply loads. Sadly, they are also ideal for things like arcing in a power strip caused by salt creep. So, a dilemma for aquarium owners.

This was my concern when AFCI breakers entered the conversation…

— thank you for so eloquently listing pros and cons!

— I think this topic could merit further discussion; finding the best of both worlds with AFCI…

 

[jonelder68]

This was my concern when AFCI breakers entered the conversation…

— thank you for so eloquently listing pros and cons!

— I think this topic could merit further discussion; finding the best of both worlds with AFCI…

I’ve had no issues so far running combo GFCI and AFCI breakers on my set up. But I do understand what Bean has mentioned.