I agree 100% on this being a cavitation issue, way too rapid for electrolysis to be the culprit.
Great video, I like them when they are short and to the point like that.
The following came up as recommended by YT while viewing your link. Another great simulation but without the veritable freak drive for manipulation and done with a pump and plumbing system designed for observation.
I'm curious with the stainless vs bronze impellers if material isn't the only difference. Could the pitch also be different and creating a different volume/flow/pressure while operating at the same RPMs?
