Ever get Zapped by your tank?
- Thread starter magdelan
- Start date
Gary Majchrzak
Team RC
IME fishes can be affected by stray voltage.
Been zapped a few times,Dropped a light in a tank and reached for it. Emptied a can of salt water and forgot the mixing pump on the bottom was pointed upward and on. So when I took out a bckett and created a shallow pool in the can the water shot up in my face and onto the power strip on the wall. I reached for the plug(bad instincts).After a stunning shock the circuit breaker blew. Broken heater got me once. I now use gfcis but they are not a replacement for a better brain.
Didn't get any special powers but I was charged up for a few days.
Didn't get any special powers but I was charged up for a few days.
Brent Thomann
New member
ironically last night I got zapped while having my hands in my tank. I have 4 tanks connected with lots of power cords running into them so it took a while using a volt meter trying to find the culprit. Ended up being a small walmart fan I had over my sump. The moisture/dew on everything under my stand made a connection from the sump to the fan motor. its probably been like this for a while so maybe my sps will color up 
acdraindrps
New member
I have seen fish swim unaffected in tanks with stray voltage, without any ill effects. If someone is prepared to prove me wrong with hard facts I would be very much interested.
what about the effects of stray current or voltage on corals? I have read many conflicting stories. One being that a small ammount of stray current or voltage can stunt the "growth" of corals although will continue to appear healthy with great polyp extension.
On the other hand, i read about expirments where in the ocean reefs, they would create metal cages for reefs to grow on that were connected to electrical current, Now wether that current was a continious or just random jolts here and there to "STIMULATE GROWTH" I don't know. ALthought they said the growth of the electrically stimulated corals was increased.
I just recently (2 weeks ago) placed a ground probe on my tank.
Occasionally I would feel a slight tingle on my finger when working in the tank at first I thought it was just how my fingers have cuts around the fingernail but when I just barely touched the surface of the water, not even past the fingernail, I would still feel a tingle at the cutical area. The tingle was very light but still irritating.
all fish are alive, no effect on the fish. Corals look great but the only thing I have noticed is coral growth has been almost NONE!
I mean not a single zoanthid, paly polyp has sprout, leathers not grown, sps not growing, candycane trumpets are FINALLY splitting.(purchased them when they had 6 heads about 1 year ago and now they almost have 9!!!) yea, I'm a little stressed about the no growth. I have taken my water to many LFS and all have tested my water parameters as VERY GOOD and are rather stumped at the reason of no growth, not to mention no coraline growth on the glass! I have tons on my 90lbs of live rock but that was there when the live rock was initially purchased....
I really don't know what the problem is.....
On the other hand, i read about expirments where in the ocean reefs, they would create metal cages for reefs to grow on that were connected to electrical current, Now wether that current was a continious or just random jolts here and there to "STIMULATE GROWTH" I don't know. ALthought they said the growth of the electrically stimulated corals was increased.
I just recently (2 weeks ago) placed a ground probe on my tank.
Occasionally I would feel a slight tingle on my finger when working in the tank at first I thought it was just how my fingers have cuts around the fingernail but when I just barely touched the surface of the water, not even past the fingernail, I would still feel a tingle at the cutical area. The tingle was very light but still irritating.
all fish are alive, no effect on the fish. Corals look great but the only thing I have noticed is coral growth has been almost NONE!
I mean not a single zoanthid, paly polyp has sprout, leathers not grown, sps not growing, candycane trumpets are FINALLY splitting.(purchased them when they had 6 heads about 1 year ago and now they almost have 9!!!) yea, I'm a little stressed about the no growth. I have taken my water to many LFS and all have tested my water parameters as VERY GOOD and are rather stumped at the reason of no growth, not to mention no coraline growth on the glass! I have tons on my 90lbs of live rock but that was there when the live rock was initially purchased....
I really don't know what the problem is.....
Brent Thomann
New member
I'm 100% confident that stray voltage caused my struggling echino frags to die slowly. As soon as I fixed the problem the few that weren't dead all the way came right back. I found that the ground probe I had in was somehow adding the voltage to my water and the stinging of my cuticles. Or maybe the ground probe was just completing the circuit?
I also noticed slow grow in corals from stray voltage.
I also noticed slow grow in corals from stray voltage.
Gary Majchrzak
Team RC
good question!
what would a powerhead leaking electricity into an aquarium be... stray voltage or stray current?
Freed
It's what it's
Current. The voltage is the force pushing the amps along. Amperage is a measure of the amount of joules passing a certain point in a given amount of time. The voltage is not what you feel, it is the amps going thru your body because of the low resistance(ohms) your body has for the current(amps) to go to ground.
Disclaimer: I have limited knowledge of this stuff but I did take some electronics classes and I DID NOT stay at a Holiday Inn Express last night.
Disclaimer: I have limited knowledge of this stuff but I did take some electronics classes and I DID NOT stay at a Holiday Inn Express last night.
Gary Majchrzak
Team RC
I believe current is the correct term....
I think that's what I called it in my original post.
http://archive.reefcentral.com/forums/showthread.php?s=&threadid=136079&highlight=stray
I think that's what I called it in my original post.
http://archive.reefcentral.com/forums/showthread.php?s=&threadid=136079&highlight=stray
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:eek1: Harmful but much more so if there was a ground which would make the stray voltage current.Without a ground the stray voltage would likely not flow very far from the source and should be relatively harmless until it finds a ground such as your bare hand while you are standing in a puddle.
Gary Majchrzak
Team RC
barehanded + barefoot on cement basement floor gave me a jolt
magdelan
Fish?
<a href=showthread.php?s=&postid=13024745#post13024745 target=_blank>Originally posted</a> by tmz
Is that why I got shocked? I was standing barefoot in a puddle when it happened.
jdieck
New member
Yes that is why as your body closed the circuit to ground and there was no device to interrupt it which that is what GFCIs are supposed to do.
So let's get some additional basic information:
1. Marine tanks and it's related equipment, due to the fact that salt water will affect most conductors / metals are mostly made using materials that are not affected by salt water which also in general are poor electricity conductors (PVC, epoxy, styrene, acrylic, ABS, etc.) so as a result a marine aquarium will be electrically insulated from ground.
2. Electricity by design has to travel in trough one conductor (hot; black or positive red line) to a device and from the device to ground (neutral white; ground green or negative; black or green)) via a second conductor.
3. A conductor conducting changing current (alternating or transient direct) will generate a magnetic field unless properly electrically shielded. In turn a variable magnetic field will generate voltage on a conductor which if grounded or in a closed circuit will generate current trough it.
4. A breaker is designed to protect the wires and trip (disconnect) if a circuit current exceeds usually 15 to 20 ampere. This can be caused by a short circuit or equipment overload.
5. A Ground Fault Circuit Interrupter is designed to protect a person and trip if there is an unbalanced current of as little more than 5 thousands of an ampere between the input conductor and the output conductor which means part of the current has been diverted from the normal path (potentially trough the person)
Now having established some of the basics I will describe some scenarios assuming there is always a functioning circuit breaker...
1. With no GFCI and No Grounding probe
Tank and system is insulated from ground. If there is a faulty wire connecting either hot or positive lines to the water or to a device which in turn can connect to the water there will be voltage in the water but no current as the circuit is not closed so the breaker does not see an increased current thus does not trip until the circuit is closed, in this situation I doubt anything in the tank may be affected as they will be in a similar situation as a bird on a wire but:
a) If are lucky and the faulty wire shorts to the other wire; hot to neutral or ground, or neutral or ground to hot) with very little resistance then the current will exceed the 15 or 20 Amps and the breaker will trip but
b) If the short has some resistance the current will increase but may not reach the tripping level, in this case your power consumption will increase, the device will not function properly and your wiring may overheat creating a second potential for a more serious short circuit or even a fire.
At increase current also, if there is a false contact in the circuit (say the plug in the outlet is a bit loose) sparks will be created at the contact point overheating, melting the contact metal or melting the wire creating a serious hazard for a fire, all this without the breaker even noticing because the current has not exceeded the limit.
c) If you are unlucky enough to put your had into the water or touch the device with the faulty wiring while you are fairly well grounded (Barefoot on a puddle as an example) you will be seriously shocked or electrocuted as the current needed for that to happen is way below the 15 Amp needed for the breaker to do it's thing so it will probably will not trip. The degree at which you will be shocked will depend on how well you are grounded. If wearing dry rubber soled shoes or standing on a wood chair or rubber mat you may not be shocked at all.
2. With no GFCI but with Grounding Probe
Tank and system is no longer insulated from ground. If there is a faulty wire connecting either hot or positive lines to the water or to a device which in turn can connect to the water there will be no voltage in the water but current as the circuit is closed. If the current is high enough the breaker will trip and the degree at which our critters will be affected depends on how fast the breaker will trip from no affected at all to fully fried.
a) If the short circuit is not good enough to create a current high enough to trip the breaker but high enough, you will be in a similar situation of 1(b) above, our critters most likely be very hurt and damaged and the potential for a fire is pretty high. This is most often seen with a faulty heater or a power head with cracked wire or epoxy insulator inside the water.
b) If the short circuit is outside the tank (say the hot wire shorts to the lighting fixture metal hood or reflector) there will be no current in the tank as the circuit is not closed via the grounding probe. In this case if you work in the water nothing will happen but because the water is well grounded, if you accidentally touch the fixture (say with your elbow) while working in the tank then you again close the circuit, in this case because you will always be well grounded (by the probe) then most likely your shock will always be serious.
3. With GFCI and with Grounding Probe
In this case any time there is some short to water, wether via wire or via yourself and because there will be diverted current to the ground probe even in small amount, the GFCI will always trip if functioning properly.
This is good as it will give you an immediate indication that something is wrong and you will not be in danger of getting shocked so it is a safe if not the safest alternative for you but you need to be around to notice and correct the fault. If you happen to be traveling and the fault happens your system may be without power for a long time. This could be minimized using different GFCI's for different pieces of equipment so not all the system turns off.
4. With GFCI and without Grounding Probe
In this case if there is a fault to the water because there is no ground probe the circuit will not be closed so it will continue operating normally until something or somebody closes the circuit. In this case the GFCI will trip. If it is you closing the circuit, you may or may not even feel a slight tingling before the GFCI trips.
In summary the safest for you will be to use GFCI and Probe but using only GFCI is a good compromise as you will be protected but the system will not trip when you are not around.
None of the cases 1 trough 4 above IMO could really be called "stray" but rather actual faulty "short circuits".
Most cases of actual "stray" voltage are caused indirectly mostly by magnetic fields or electrical noise.
Some classical examples are the voltage created on a metallic reflector by the magnetic field around the bulb. In this case there will be voltage in the reflector which if touched and you are grounded it will give you a shock similar to the shock of the spark you get when charged by walking on a carpet on your socks and then touch something or someone grounded.
Note that by definition stray current will be the one created by stray voltage and will happen only if the circuit for that voltage is closed (reflector>you>ground).
Although stray voltage per se could be pretty high the current it generates it is either only instantaneous; like the carpet rubbing case of voltage capacitive discharge, or rather continuous but very small; like the inductive case of the reflector which can easily be avoided just by grounding the reflector.
In my opinion the only concern with capacitive or inductively created stray voltage is really that it can create false tripping of the GFCIs. Also false tripping can be created by unfiltered noisy devices (cheaper ballasts are typical for this).
Hope this info can help to clarify a bit some concepts but by no means should be interpreted as a stated recommendation and if you have any doubts about electrical safety of your system I would recommend you consult with a local licensed electrician.
Enjoy and Be Safe!
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