Boomerius

I see - thank you Well so wouldn't the water which is connected have the same reduction potential all over as long as it's connected, no matter how far? or would that measurement also change over distance on the water?

I am new to the field, so have been trying to find out about Earth's reduction potential. I couldn't. So maybe you know the answers to following questions : Earth reduction potential: - does it have a single one (or maybe it differs depending on a location) - if it does have one, what is it? (in mv) - does it differ in natural pools of water (Rivers, Oceans, lakes)? - anything about natural Earth's reduction potential?