I'm going only by how I feel, too. I think the foot bath is producing improvement. I think it will take a little time
I am not sure this color business is as important as a lot of folks seem to be assuming, in fact I am about to decide there's something else going on entirely. When I finish with it, I'll post and see what y'all think :).
Since the lifespan of a set of S/S electrodes is finite, it stands to reason that some component of them is being dissolved into the foot bath water. That's OK with me, as long as I feel improvement.