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

  1. Mar 22, 2015 #1
    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 wont light up.

    What am I missing?
     
  2. jcsd
  3. Mar 22, 2015 #2

    davenn

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    hi there
    welcome to PF ")

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

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

    would you like to try again ?

    cheers
    Dave
     
  4. Mar 22, 2015 #3

    phinds

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    Crappie are fish. I think he wants to electrocute them.
     
  5. Mar 22, 2015 #4
    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.
     
    Last edited: Mar 22, 2015
  6. Mar 22, 2015 #5

    davenn

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    Yikeees :frown:
     
  7. Mar 23, 2015 #6
    It does not kill them if done right. thats 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] [Broken] 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 cant 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!
     
    Last edited by a moderator: May 7, 2017
  8. Mar 23, 2015 #7
    I dont know how to make a drawing on a pc. I'm sure its simple but I still have a flip phone.
     
  9. Mar 23, 2015 #8

    jim hardy

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    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 couldnt find a "holdem" manual. Who knows what names they gave to their two HV terminals.
    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..
     
  10. Mar 23, 2015 #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?
     
  11. Mar 23, 2015 #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.
     
  12. Mar 23, 2015 #11

    berkeman

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    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?
     
  13. Mar 23, 2015 #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.
     
  14. Mar 23, 2015 #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.
     
  15. Mar 23, 2015 #14

    berkeman

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    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?
     
  16. Mar 23, 2015 #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 dont understand what it does. I'm a 100 ton master captain but electricity has always thrown me off.
     
  17. Mar 23, 2015 #16

    Doug Huffman

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    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. Mar 23, 2015 #17
  19. Mar 23, 2015 #18
    where would I find one? Could I make one? Thanks for your input and knowledge!
     
  20. Mar 23, 2015 #19

    Doug Huffman

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  21. Mar 23, 2015 #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
     
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