Acid-stained concrete has been popular for decades. The process of acid staining is well documented, as are the key precautionary items to look for before and during application. When I first started troubleshooting decorative concrete problems around 2001, I got a lot of calls involving acid stains. oday, I might get these calls a few times a year. Thanks to real-world experience, continuing education and better specifications, issues with acid stains have been greatly reduced.