Alright, so to followup on my previous thread, I went with the general consensus and did an Oxalic Acid bath to de-rust my frame. I'm halfway done before I can pull it out, but I was wondering what I should do about the residual buildup on the frame.
I've seen and can get rid of the yellow powder chunks and such, but what I'm talking about is white. Almost like a fog on the frame, but only on the painted surfaces. From spot testing, I can't get it off with a light rag, nor a medium toothbrush. I tried a brillopad, and it sort of worked, but I didn't want to mess up the paint. It doesn't engulf the frame, but there is quite a bit of it is placed throughout the surface of the frame.

I was curious if any of you had experience with such a thing, and how you dealt with it.

Thanks in advance.

Oh, and the tub isn't metal, well, it is painted steel, but I put a plastic liner in it, so I don't think it's anything battery like.