Pond Boss Forums GENERAL QUESTIONS Pond Boss Question for the electrical enginners here...

A GFIC tripped at the latest high school I set up an RAS with and killed 50 good size tilapia. I refuse to not have this safety measure for obvious reasons. Mainly I don't want to get anyone electrocuted and be involved in a law suit and lose everything I own.

It went for a couple of months with no issues and then when no one is around for a day it tripped, so I don't think the GFIC is defective. And of course with no one to reset it the battery back up ran for several hours and ran out of juice. It doesn't seem to take much to trip these things and in my own facility I refuse to have one and will take my chances.

Anyway there will be no more fish unless the school funds some kind of alarm dial up system. So far they haven't spent a dime, and with four schools I'm tapped out.

Was thinking of the following as it is cell phone and text capable:

http://store.aquatechnologygroup.com/products/gfci-trip-alarm/

Thoughts?

GFCI's trip, but you have to remember that you are installing systems in schools where many people gather, and possibly poke around in the tank with water.

You got more than a GFCI installed, like a gizmo that will shunt trip the mains?

GFCI's don't always work, so you need to back yourself up.

No way would I put something in a school, unless they understood everything, and that would include electrical!!!

That looks good to me as a stand alone system that monitors the GFCI receptacle. I have seen GFCI trip randomly for no reason I could find, but sometimes it is caused by a tiny amount of intermittent leakage to ground in the load. I bet the school doesn't have funds to pony up the cost, or the powers won't think it is worth the cost. There are good reasons not to use GFCI receptacles for essential equipment. In my experience, GFCI circuit breakers are a little less prone to tripping, especially if dedicated to one feed. I would never plug my refrigerator or freezer into one, but school aquarium systems are a different story.
Another thought: the UPS could be re-worked with a large deep cycle 12 volt battery and trickle charger. That would give you about 10 to 15 times the run time of a standard UPS, and still preserve the switching and alarms of the UPS.
Good luck.

Very true! That's why I want a GFIC! Just noticed at one of the other schools some idiot was plugging up a screen in the mbbr with chewing gum!



Not that I'm aware of but this is an old antiquated part of a new school so who knows?



Yeah I hear they can be defective at times. This one apparently worked just fine!



You're smarter than me in more ways than one! Three schools was enough of a hassle, but these guys had a tank from a previous teacher and begged me to help set them up. The kids do love the fish and it is a way to learn several disciplines at once. Some are now interested in fish farming.

Thanks for the info John in addition to Phil's.

So far all has been on my dime. Our state politicians talk the talk about funding education but they are actually doing just the reverse.

Keep it safe for everyone to learn!

Last time I ate some amps, not fun at all!!!, and AC amps are an equal opportunity source to mess you up.

It was a couple days before the nose bleed lightened up, and about a week for the brain fog to clear.

Yep, don't want to get hit like that again!!!

You're preaching to the choir on that one! Principlal wanted to know why we needed a GFIC anyway.

Seriously?

I remember when I learned to wire an electrical outlet, 1964. My mom and dad bought the 150+ year old farm house that had been in the family since it was built. I was around 9 years old. The house didn't have any electricity so we had to run wire thru the whole thing. My uncle was teaching me to install outlets as that would be one of my jobs. So we hunkered down next to a box and he asked a guy working with us if the power was off. The guy grabbed the two wires and said NO. He didn't even blink! Yes, the power was on!

Sorry Cecil! Not hijacking the thread but sometimes things just bring up old memories!

"Every time Catherine would turn on the microwave, I'd piss my pants and forget who I was for about half an hour..." Eddie from Christmas Vacation.

Sorry. Couldn't resist.

Looks like that gizmo might be the most reasonable recourse.

If it were me, I would build my own little box that everything plugs into. Run a dedicated line from the CB panel with a NON GFCI CB. Inside the box use a GF Sensor with some safety circuitry. If it is a real ground fault, it will drop out power. If it's a nuisance trip, either ride it thru or automatically reset after a time delay. This is a built in feature in my pump drives.

I just ran across this web page the other day, and it kind of goes along the lines of this topic. Could it be why it tripped? ... And what do you guys think about their solution?

I wonder if this stray voltage applies only to salt water or could it apply to our systems too.


Taken from "aquartaquariums":

Voltage can enter our aquariums by several means, one of the most common is induction. Induction is the process by which an electric current, an electric charge, or a magnetism is produced by the proximity of an electric or magnetic field. Let’s see; do we use any magnetic fields or electric charges in the proximity of our aquariums? You bet we do. Power heads and large water pumps have both. Fluorescent lights have a strong electric charge in that tube. As air bubbles burst at the surface of the water they spray salt several inches. Salt creep or salt spray can form and give electricity a path from lighting, heaters and powerfilters to find the aquarium water. Because of the conductive properties of salt water all equipment (heaters, lights, powerfilters etc.) should be kept clean of salt spray and salt creep. Non submersible heaters should never be used on a marine aquarium. Not only because of the potential of stray voltage in the aquarium but they will eventually stick in the on position.


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Now we know were it comes from so how do we test for it? Using a voltage tester or volt meter set to read AC voltage (VAC) put one lead on a known ground and the other in the tank water.

The first tank I tested was my 125 gallon reef tank. The tank is acrylic and sits on a wood stand. All lighting is suspended ten inches above the tank. I use an Iwaki pump for water return and three Maxi Jet power heads in the tank for circulation. I have a 300 watt submersible heater in the sump. After finding a good ground I set the volt meter to VAC and to my surprise I had 12.5 volts. Intrigued by the amount of voltage in my tank at home I thought it would be a good idea to check all of my marine tanks at work. I found every marine tank has some detectable stray voltage, from .63 VAC on a twenty gallon tank to 43.62 VAC on a 110 gallon wall unit. Even at nearly 44 VAC we did not feel any shock when we put our hand in the water, I wouldn’t try it barefoot.

Next step was to eliminate the stray voltage. On every tank I unplugged each piece of electrical equipment one at a time wile testing for voltage. On most tanks it was a combination of every appliance leaking or inducing voltage but in some cases I did find faulty powerheads and even a few faulty submersible heaters. Once faulty equipment was ruled out or replaced I needed to ground every tank’s water. At the time of my testing commercial ground probes were not available. I used a length of stainless steel wire, one end connected to an electrical ground and the other placed in the aquarium water. Since the current travels through the entire system there is no need to put the ground in the tank. I prefer the ground probe to be in the filter or sump. Several companies have since come out with ground probes. The most popular design is a titanium probe that will be in contact with the water. Copper wire runs from the probe to a spade connector that you attach to an electrical ground.

If it does not shock us, why do we care if we have voltage in our aquariums?

Fish have a sensory organ called the lateral line complex. With this organ the fish can detect pressure changes in the immediate vicinity, from the movement of currents or from other fish. It is also used for navigation, finding food and avoiding predators. In most fish this lateral line complex can also detect or sense electrical charges in the water. If you have any stray voltage in the water it can overwhelm this organ, much like living in a deafening noise environment. This will cause stress, and among other things, suppress the immune system making your fish more vulnerable to natural bacteria and parasites which occur in every tank.

On my first test tank, my reef, I had a yellow tang that I would say was skittish at best. You could only observe this fish if he did not see you. Immediately after grounding this aquarium the yellow tang would swim in front of anyone without fear.

Stray voltage has been speculated to be one of the factors that can cause Hole in the Head and Lateral Line Erosion (HHLLE).
Stray voltage is something that exists in every tank. Stray voltage can be eliminated with a simple ground probe available at most pet shops in the twenty dollar range. Elimination of I wonder if this stray voltage applies only to salt water or could it apply to our systems too.

stray voltage is a simple step in reducing the stress on your fish. Every marine tank should be grounded for you and your fish’s protection.

First off I would never use a plug GFCI. Get your self a GFCI breaker and put it on that whole circuit. The plug GFCI can trip like an arc fault as well for no reason and for this reason they are junk.

If the GFCI breaker trips you do have a direct fault and need to source it out.

Have a second breaker that you can switch to if you have the first to go down and when you to get the alarm text you can just swap plugs to eliminate the problem or run your back up off the second circuit.

Cheers Don.

Thanks Don and others for your responses.

Unfortunately it's up to the school if they will put in a GFIC breaker. It was the best I could do at the time I set up the system. They claim they have no money.

If your system was working fine then out of the blue started to trip and it is not a faulty GFCI plug check all submersible pumps for water in the encasing oil. Happens all the time.

Cheers Don

As a side note, GFI can trip from a simple static discharge on an appliance as well. If it forms a spark between hot and whatever, that brief change in current can be enough to trip them.

Also my upstairs aquarium acquired a leak in a Fluval canister filter and went across the floor and under my timer outlet. It tripped the GFI since water got into the outlet... right under the carpet where I am currently typing. I am quite glad it tripped, so they are of use for sure.

Thinking about this a bit though, it sure would make sense to use isolation transformers and low-voltage to run aquariums rather than directly from 120VAC.

When I was a kid, I broke a glass water heater when cleaning my aquarium. I was very lucky as it has become unplugged when I was working behind it. Imagine one arm in the water, the other resting on something conductive... Makes me break a sweat thinking about it.

I had one trip at the old house do to a short in an outlet on the deck. Problem was the actual GFI outlet was in the garage on the other side of the house. Took me a couple of hours to find it!

I just tested the voltage in a 40G aquarium downstairs. Got 0.74 volts. Unplugged one of the heaters and it went to 0v. When I first plugged it in, I could feel a bit of voltage when I touched it under water, then it went away.

That small of voltage is due to capacitance between the coils of the heater and the water with the insulator of the heater in-between. The current will be minimal and therefore harmless to us.

That stray current theory is interesting for fish behavior. That is how they detect predators and also perform some communications (you've seen fish do the "twitch" dance). Maybe I will try grounding my aquarium and see what happens as I have occasional inexplicable deaths and generally the aquarium does not thrive as it should.

It may simply be best to put in a grounding rod, but please note: That material you use is critical! Corrosion of metals can be poisonous to fish and/or plants. Don't use copper, as that will kill the plants. Don't use zinc, as that will actually make the problem worse as it corrodes. Use something gold-plated or platinum would be ideal. Stainless is OK, but it can still produce metallic ions in the water. The commercial titanium would work well as mentioned. The best material may be something cheap like a pencil lead (graphite) or a carbon rod of some kind. They are conductive enough for what we are trying to accomplish and completely non-toxic.

You should ask one of the guy's at work what induction is all about.

Working at a waste water plant a few years ago. New controls, but using the same underground wires that run up to 4000' in the same conduit. Power was hot because we couldn't shut the place down. Isolated I/O and Interposing relays so we could do it hot. Quite a few wires were disconnected on each end to tie in the I/O, but never dropped power.

It's miserable out, raining, cold and such. He's wearing sneakers that are wet. Keeps saying ouch and put's wire nuts on everything he says is hot.

I know these wires are not connected to any power source on either end, but the induced voltage, virtually no current, will give you a poke.

I grabbed one of the wires he said was hot (after measuring it tho), extended my right index finger and touched him on the shoulder a few times. He said don't do that! I just told him you should not be out on a live site with wet tennis shoes. He called me a prick and a few other choice words, but if he actually grabbed the wrong wire in that live mess...

Sometimes it takes a prick...

Update: The school has invested the $219.00 for the following unit, and the $34.99 a year for cell phone text service. Testing shows it not only will text the teacher if the GFIC is tripped, but if power is cut to the system as well, as in a power outage. Then there is an inverter and batteries to take it from there for up to 5 hours until the school's back up generator kicks in. Apparently the delay in the school's backup generator is to conserve energy until it is really needed.

http://store.aquatechnologygroup.com/products/gfci-trip-alarm/

The next step is to change from the GFIC extension cord to a decated in circuit GFIC. The teacher assured me it would be done.

Thank you all for your input!

Now I need to transfer 154 four to seven inch YOY bluegills from a smaller to a larger tank in the basement, and order and get about 150 Tilapia fry Fedex overnight and plant them into the smaller tank. Once they are a solid 3 to 4 inches I'll transfer some of them to the school.

All tilapia that survive the four high schools until the end of the school year will be sold for algae control. Already have a buyer.

I'm telling you guys when it comes to rearing fish in closed systems Murphy's Law applies! And you will kill fish sometime in the process. It's a given!

Btw the GFIC trip may have been triggered by power down of the school during Christmas break (as someone here suggested) as it hasn't happened since.

A WAG on my part as I'm no way knowledgable other than basic electricity, but it sounds good enough to me. Who knows maybe someone shut down the power and doesn't want to admit it? Had a bean counter come through and shut off the power to air pump that was keeping a biofilter alive for the summer at another school.

Regardless it's water under the bridge and we seem to have the bases covered at this particuar school.

Oh had a brief power outage at another high school and the following inverter and two batteries wired in parallel saved the day. Once power was restored the inverter charged the batteries back up. That school invested in an alarm dial up to the teacher and all the maintenance guys!

inverter http://www.tripplite.com/inverter-charger-750w-automatic-transfer-switching-2-outlets~APS750/

Sounds reasonable for what it is doing.

Speaking of induction. We were thrashing on a fiberglass body of a funny car in my shop. My buddy put his hand into a pail of water we had out there to wash them. He said when did you get hot water in the shop. I said we don't have hot water out here. He said he washed his hands in that pail of hot water. Walked over to the pail and the end of an extension cord had got hung into the bucket by accident and heated the water up. It was such a late night work thrash that he washed his hands in the bucket with out noticing the cord hanging in there plugged in.

No shock with a good ground but heated the water up.

Cheers Don.

Looks like a good solution to me Cecil. Glad you are getting rid of that extension cord!

Yikes!!! I know how it is working all hours of the night to get a car ready.

Last time I drained my pond I had tank of water on the pond bottom, and when the water level got down to nearly nothing I walked around on the pond bottom and flipped large fish into the tank to save them. Had a long extension cord on the pier down to a sump pump that was circulating water in the tank. Put my hand in the tank and I felt an uncomfortable amount of electric current. Not terrible but not comfortable. The fish in the tank didn't seem to mind.

I immediately unplugged the sump pump. Last time I posted that here JKB said I was lucky I was wearing rubber waders.

I was careful to keep the cord connections out of the water, but part of the pier is alluminum and there may have been damage to the extension cord.

There is a GFIC but I'm pretty sure it needs to be replaced and doesn't work!

Will never do that again! We've had lake people electrocuted here.