I have a customer who wants a stain from his concrete front porch removed. He bought a cheap door mat and when it got wet the die ran off and stained the concrete. I tried Pressure, Gutter Grenade, Simple Green and SH with no luck. Anyone have any suggestions? I don’t have hot water. My last resort is mauratic acid.
Could try barc-9, looks like a rust stain
Not sure if you’ve fixed this yet, but I did the same thing on my new concrete porch and used Stain Solver (stainsolver.com) to get it out!