In this picture you will see that we have added water to the section of the large plastic container next to the sand.



This has not made any differecne to the water levels in any of the other containers.

It does make it impossible to measure to the bottom of the submerged container.

The water distorts the view of the glass by refraction of the light.

In cathodic protection monitoring there are a number of influences that distort the accuracy of the voltage shown on the meter.

These have been bundled together and called "the IR Drop in the Soil"