Ok, hello for starters I have a question about water/electrofishing

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In summary, The person is trying to reduce the number of crappie in their pond by using an electric fence. They connected the fence to a 12v deep cycle battery and tested it at home. They took the fence to the lake today and tried different ways of grounding it, but the power light on the fence controller wouldn't light up. They are wondering if they are missing something, and if so, what it is. The person suggests trying different lengths of wire to see if that solves the problem, adding wire screens to disperse the current better, or finding a way to generate an electric pulse.
  • #1
Iseepotential
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I have a private pond and want to reduce the number of crappie. I took a model 57 hold 'm electric fence controller and via inverter connected it to a 12v deep cycle battery. I tested it at home in a 1 gallon mason jar of water with two "hot" leads in water and the ground to a cabinet hinge and it worked great(both lights saying good power and ground. Took it the lake today with a 10 foot devider and silver solder 4 pronged things off each end connected to the two hot wires and tried about twenty ways of grounding it. The power light comes on but the light that signals signal strenth won't light up.

What am I missing?
 
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  • #2
Iseepotential said:
What am I missing?

hi there
welcome to PF ")

... a better explanation of what you are trying to achieve

Iseepotential said:
I have a private pond and want to reduce the number of crappie

I cannot even begin to imagine what on Earth you are talking about ??

would you like to try again ?

cheers
Dave
 
  • #3
davenn said:
I cannot even begin to imagine what on Earth you are talking about ??
Crappie are fish. I think he wants to electrocute them.
 
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  • #4
Iseepotential said:
I have a private pond and want to reduce the number of crappie. I took a model 57 hold 'm electric fence controller and via inverter connected it to a 12v deep cycle battery. I tested it at home in a 1 gallon mason jar of water with two "hot" leads in water and the ground to a cabinet hinge and it worked great(both lights saying good power and ground. Took it the lake today with a 10 foot devider and silver solder 4 pronged things off each end connected to the two hot wires and tried about twenty ways of grounding it. The power light comes on but the light that signals signal strenth won't light up.

What am I missing?
Do you have a drawing? Have you considered the conductivity of the water? Have you considered that the electrodes have to be close to each fish? 10 feet seems a bit far. I am thinking that since the fence charger is designed to give a jolt without killing something and that a sustained lethal current should be used because it is the amount of current through the body that kills.
 
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  • #5
phinds said:
Crappie are fish. I think he wants to electrocute them.

Yikeees :frown:
 
  • #6
It does not kill them if done right. that's how fisheries biologist check the health of a body of water. it just stuns them for about 30 seconds. Heres a patent for something similarhttps://[URL="http://www.google.com/patents/US8091269"]www.google.com/patents/US8091269[/URL] It takes a pulsing charge to achieve the desired results. Crappie are indeed a fish and they are extremely prolific breeders. A 3 year old female will lay up to 100,000 eggs and a first year fish around 25,000. I don't want to kill anything really. Just get a handle on the overpopulation problem. The fence thing may not work...I just can't understand why I can't ground it. I am open for any suggestions. Even taking the damn thing apart or starting from scratch. I hate buying premade stuff...I'd rather learn by doing it myself. Thanks for the replies fellas!
 
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  • #7
I don't know how to make a drawing on a pc. I'm sure its simple but I still have a flip phone.
 
  • #8
Only guessing here

i searched on "electric fence grounding"

and it looks to me like one side of the HV winding should be tied to earth
and the other side of HV winding expects to be tied to an insulated wire.
http://www.fs.fed.us/eng/pubs/htmlpubs/htm99232321/
http://www.fs.fed.us/eng/pubs/htmlpubs/htm99232321/fig1.jpg

i couldn't find a "holdem" manual. Who knows what names they gave to their two HV terminals.
Iseepotential said:
Took it the lake today with a 10 foot devider and silver solder 4 pronged things off each end connected to the two hot wires
What's a devider? A wire screen?
If you connected both HV terminals to same piece of wire i would guess that places a dead short across HV winding.

Pond water itself might conduct enough to overload the charger. Check by tryng the same length wires that you used in the mason jar for starters..
 
  • #9
like a T mounted to the bow of the boat with the same wires I used in the jar. I just added the 4 pronged solder things to try to disperse the current better. The only difference I can come up with is a greater volume of water so its not completing the circuit?
 
  • #10
would the amount of water being conducted make a difference? Stupid question I am sure. Of course it will, does anyone know how to make an electric pulse generator? I am certain I am going to do this one way or another and I figure you guys are as smart a bunch as I am likely to find.
 
  • #11
So what is the point of stunning the fish, if not to make them rise to the surface to be harvested? Is it going to scare them away or something? What is the end goal?
 
  • #12
to selectively harvest fish with a net. I want to keep the florida strain largemouth bass in thye pond as well as the coppernose bream and blue and channel catfish and reduce the population of crappie. The end goal is a healthy lake we have invested about 30,000 in creating and stocking. And yes for about 30 seconds they come to the surface and can be netted. If I understand this whole thing correctly it(the hot leads)creates a magnetic field that screws with their internal compass as the leads pass over them. You have heard of cranking a military grade telephone to stun fish right? Same idea.
 
  • #13
The crappie are so prolific they eat all the forage fish and it turns into a pond of small crappie. They eat everything else.
 
  • #14
Iseepotential said:
It does not kill them if done right. that's how fisheries biologist check the health of a body of water.

Iseepotential said:
to selectively harvest fish with a net. I want to keep the florida strain largemouth bass in thye pond as well as the coppernose bream and blue and channel catfish and reduce the population of crappie. The end goal is a healthy lake we have invested about 30,000 in creating and stocking. And yes for about 30 seconds they come to the surface and can be netted. If I understand this whole thing correctly it(the hot leads)creates a magnetic field that screws with their internal compass as the leads pass over them. You have heard of cranking a military grade telephone to stun fish right? Same idea.

So what equipment do the fisheries biologists use? Do you have any pictures? It would seem that you should just try to duplicate what they are using already, no?
 
  • #15
thats what I'm trying to do. I'll look up some pics. They use a generator and a controller of some sort. I don't understand what it does. I'm a 100 ton master captain but electricity has always thrown me off.
 
  • #16
Electric fences are low current at high voltage. Surplus phone generators are common and a better answer. How about a hot side 120 VAC from the mains, maybe with a light bulb current limiter. Dip the lead momentarily and shut off the supply.
 
  • #18
where would I find one? Could I make one? Thanks for your input and knowledge!
 
  • #19
http://www.ebay.com/itm/Vintage-HAND-CRANK-5-BAR-MAGNETO-Western-Electric-TELEPHONE-GENERATOR-48-A-Nice-/321699786017
 
  • #20
wow, cheaper than I thought. Thanks alot! I still want to understand how it works and try to build one. I'll order one of those and take it apart, thanks Doug!

Mike
 
  • #21
would the magneto work better or do they all have magnetos? I can catch any fish that swims and now run a finance company but electricity has always given me a headache...I appreciate you guys help more than you realize.
 
  • #22
Magneto is a technical-ish name for a permanent magnet alternator, a generator of alternating current. That's the pulses that you want to stun your fish. The contrary is a dynamo a similar device but with commutator bars to making DC.

You might have noticed the change from dynamos to magnetos, from generator to alternators, in automobile motors.
 
  • #23
knew I should have paid more attention in school
 
  • #24
so I could run wires off an alternator in theory?
 
  • #25
LOL If you're still sailing on your 100-ton ticket you're making better money than the rest of your classmates.

When we were moving into our beautiful cottage, we found the builder's AB ticket from when he went sailing on the Great Lakes when he was 16 y.o. He could build anything.
 
  • #26
alternating current is what I want right? Direct won't work right? So I can't just rig something off of 12v?
 
  • #27
Like in your car? Yeah, but in the car its regulated to about 12 volts and rectified to DC. There are kits to modify them to 120 VAC.
 
  • #28
Nope. Like I said, 120 VAC from the house-mains might be simplest. Talk to your neighbor the electrician.
 
  • #29
I fish, captain(sportfishing mostly) and would have starved after potus was elected. Dying industry. I didnt have any wish to be a bus driver for rig people(dying industry with oil prices as well) Its easy to sell money;) plus i have a 1 year old son...need steady income
 
  • #30
had it rigged from 12v to a 100 amp inverter
 
  • #31
Maybe that might work.
 
  • #32
it didnt, lol
 
  • #33
something about my set up was off
 
  • #34
D'you mean the fence charger? No. Just dip the 120 VAC 100 Amp leads momentarily and far apart, across the pond from each other.
 
  • #35
Iseepotential said:
alternating current is what I want right? Direct won't work right? So I can't just rig something off of 12v?

Please do a bit more reading, now that we know the correct term is "electrofishing". Wikipedia has a good article about it: http://en.wikipedia.org/wiki/Electrofishing Including links to more information. It appears that the waveform probably should be pulsed DC, with the waveshape having an effect on the size of the fish that are attracted/stunned.

And here is a regulation from the Fish & Wildlife Service about electrofishing, although it appears to be mostly about safety aspects for its own F&WS employees when they are electrofishing as part of their conservation work: http://www.fws.gov/policy/241fw6.html

:smile:
 
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