I have studied these videos a fair bit and calculated resistance values at different voltages as per the video with AC, monitoring the resistance change. Here is what I found;

25V = 170000 ohms

49.8V = 171724 ohms

100V = 166666 ohms

150V = 166666 ohms

200V = 166666 ohms

225V = 164306 ohms

250V = 163265 ohms

287V = 163068 ohms

So for this I have come to the conclusion that whilst it doesn't quite follow ohms law the resistance does not decrease by much at all and stays in a fairly small range (in the end only by like 8,000 ohms.) My question is is this what would normally happen that it only strays from ohms law by a little bit and what is the reason it strays from it but not by much? Also why does resistance remain at the same value for a bit? And would increased salts or any other substance in the water affect how much it deviates from ohms law?

Hope I have made the question clear and understandable