The rust is caused by irrigation runoff. I tried my go-to irrigation rust remover and it didn’t even phase it. I brushed it in, let it sit. No go. Not sure what to try on this type of driveway. Has anyone removed rust from this type?
What’s your go-to? Oxalic acid hasn’t failed me yet.
I use Oxalic Acid. Works great.
I can’t recall the name at the moment. It’s a local product.
