Good catch Zoran, you wouldn't want to come across that 30km off the coast!
Not sure about your definition of a pin hole though, to me that just looks like hole, I don't think it would stop if I put a pin in it π€¨π
Thanks a heads up on that material, I use Devcon liquid steel for a metal repairs & once it hardens it is literally is like steel but not sure how exposure to fuel would affect it?