How to clean bricks

It's a build up of sweat which releases from the bricks Sykes out of the bricks a jet wash will help to get rid of it the best solution is brick acid and brick cleaner which soaks into the brick and prevents it from sweating. Once you apply the stuff to the bricks and leave it to soak in you can then clean the bricks off.

To remove paint from brick you can use Nytromors paint remover or brick acid But be very careful and follow all instructions or hire a professional.

This is called efflorescence it’s a build up of dry weather or area causing the brick to produce moisture known as salt brick acid and water won’t prevent this substance a simple dry brush or clear repellents such as silicons or acrylic coatings may help you.

Brick to Brick and vibration take the rest

Like buildwells said it’s efflorescence acid won’t help. I was once told white vinegar can help remove it but unsure if that was a true fact or not but don’t put brick acid on it