There is more than one band called ACID:
These are photos from concerts where Acid played, so they may be of other bands that played the concert as well.
Black Sabbath / Diamond Head / Acid Oct 1, 1983 Brussels, Brussels Capital, Belgium Uploaded by Bri Kel
Black Sabbath / Diamond Head / Acid Oct 1, 1983 Brussels, Brussels Capital, Belgium Uploaded by Zimtrim