Ok, I guess people didn't like that one. Does no one call bad spattery welds pigeon $#!t? I'm just making fun of my own soldering job.
Anyway, I thought I had A pinhole. Finally got around to taking a torch to the tank, poked around at some fishy spots in the paint and found about a dozen more places where it rusted through including on the side. Patched those up and next the tank's getting electrolysis. If it doesn't just disintegrate from that, whatever new holes appear are getting solder. Might just redo the welds I have there too, maybe with flux applied to the inner side of the hole for better coverage. After that, sealing.
Any pointers?