These types of algae issues need to be manually removed as much as natural. The crabs and snails will simpley not be able to cope if too long. If you keep it closely cropped to the rock, the "crew" will be much more affective. Using a new toothbrush, you can simpley wrap the bristles in the hair algae, twist and pull. This also help in not spreading the alage further.
Usually these types of algae are due to higher nutrient as well as phosphates. Have you tested for nitrate and phosphate and are you using RO
water for top offs and changes...?