We do what we do and we dont have to explain why we do it.
I know that sounds a bit like a dictatorship but sometimes we have to step in like this.
your fence thread was locked because there was no more useful information being conved and only further breakdown in order was comming out of it.
Putting some electical device on top of your tank is insane because the water will only surve to amplfy the electrical current.
Fish are EXTREMLY sensitive to electrical current even as low as millivolts. GIving them a jolt at say 19V or what ever those things put out would surly mean death. If not death then such internal damage that the fish could no longer swim correctly.
WE are all serous aquarists and many of us take such extreme posts as an offense to the hobby. There are way to many people in the world that feel fish are some lower form of life and dont deserve proper living conditions.
The thread was locked because of what I outlined above. It will NOT be unlocked and I request we move forward and not discuss such things like invisible fence over your tank again.
Thank you for your understanding.