How to Clean Grout Comparison on Tile | Vinegar, Baking Soda, Acid, Alkaline, Bar Keepers Friend

My grout is really dirty, so I tested out several products to see which work the best. I compared a commercial acid and alkaline product against vinegar with baking soda and also oxalic acid (bar keepers friend). For the acid and alkaline products, I compares clean with a sponge against using a nylon brush attachment.