Use water to wipe the walls to ensure that after washing the walls MUST be clean of lime dust or bondasing (rub the walls with your hands or a white cloth to ensure that the walls are completely clean of lime dust)
Mix the anti-efflorescence paint well with the hardener don paint on the problematic wall. Let dry in 6 hours to a day.
Color the walls with your choice of color with Grod Royal Epaini or just leave the walls using silver colored anti-efflorescene without having to paint royal.