Rust remover is a misnomer, the rust is not removed but the colour is changed in the application,the rust itself remains which of course means if the job is not done properly the mark can return.
Prochems is good and has a ph of 2.5, after application flush out with a plain water rinse.
(I think Phil means rinse out the acid not use an acidic rinse, at least I think thats what he means
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