[quote]
The water was from my backyard goldfish pond.
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What would be interesting would be to do a similar experiment but this time on human blood.
But don't cheat, only use a current with the same maximum allowed intensity that a user of a zapper is able to take without pain or damages to the skin. From my tests, i think that with 2 handholds, up to 20mA is ok.

See what it does to the human cells and to the others organisms in the blood.

I will also try this is guess, thanks for the idea. :)



[quote]
I also zapped the same water sample under the microscope and observed that the microbes died.
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What do you mean by died ?
Exploded ? Damaged ? Not moving anymore ?



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One interesting comment: I have not had much luck killing amoeba. They seem to react a bit and then go about their way.
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Maybe this means that a specific frequency is important after all, or maybe this means the intensity was not high enough, you have not mentionned what was the intensity of the flowing current.



[quote]
voltage vs time to kill, current vs time to kill, frequency vs time to kill, effect of DC offset,
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I don't understand you obsession with the voltage, the voltage is only one part of the equation and must be high enough depending on the resistance of the body where the current will be put.
The goal is to have a moving charge (or flowing current) with a high enough intensity so that it propagates the wave and the resulting vibration in most parts of the body.
I don't understand the point to study the effects of a high voltage, let's say 220V with tiny electrodes put on a dry skin... The resistance will be too high, the flowing current will be too weak.
But i think there is a point to study the effects of electric signals with currents of different intensities (of course you will have to either increase the voltage or decrease the resistance of the body) because maybe a high enough intensity has the ability to break some molecules or to alter some life mechanisms (like the heart beat).

That's my thoughts.