"Lord Kelvin water dropper."
Ok, lets talk about this, in order for the water to charge, it needs to be an isolated drop, meaning that drop can't not touch anything that conducts, once the drop of water touches anyting that conduts, it will lose its electrostatic potential.
Now there is no way in hell a low power circuit is going to be able to put 20KV between a body of water (water between 2 conductors), beliave me I have tried really hard.