The other day, while watching a fishing program on TV, they were doing an advertisement on a certain brand of fluorocarbon and did a demonstration of how it will disappear under water by having a glass of water on a table and took a piece of their line with a lure tied on it and dipped the lure into the glass of water and it did seem to disappear. This inspired me to do the same thing, so, I took 3 different brands of fluorocarbon, tied a subsurface fly on them and dipped them into a glass of water and all three fluorocarbon lines were very visible looking at them through the glass. I even tried mono to see how much more visible it was and and did not notice a difference between it and the fluorocarbon.

Are we assuming that fluorocarbon disappears under water due to the marketing hype and there is not that much difference between it and mono? I am not making any statements here based on my limited experiment, but, just wondering if anyone else has tried this and what their results were?