No. I think it was from the Stax rock I used. This is all cut with a band saw most likely which may have left some sort of residue (purely speculation). Pulled all magnets, replaced all in tank pumps, heaters, and anything else that wasn't nailed down. No rust to be found. Really no idea but it has cleared with metalwork and cuprisorb.Thats wild that so many of us had a tin crash. Did you ever identify root cause? I either forget or missed it. Rob had rusty butt magnets. Mine was fuge light and/or amazon vinyl tubing.
Sent in an ICP a couple weeks back and will see what happens.