Why is kombucha leather mostly brown? I see that KombuchaArt generates so many gorgeous colors in theirs (see lead image)? The image below is from http://www.instructables.com/id/Kombucha-Fabric/

Why is kombucha leather mostly brown? I see that KombuchaArt generates so many gorgeous colors in theirs (see lead image)? The image below is from http://www.instructables.com/id/Kombucha-Fabric/
