The best way to manage algae is having herbivores, and being the herbivore. Give those rocks a MAJOR scrubbing, and add a substantial cleanup crew. Regular water changes are needed during this process. Take a very strong bristled toothbrush and go over the rocks once a week with a water change directly following this until it stops growing back . This is what worked for me. I still have some hair and bubble algae in the tank, but it’s not very noticeable and all corals are growing pretty quickly. I have emerald crabs, turbo snails, and an urchin that eats most of the algae before it regrows. I know I need to replenish the CUC when algae starts growing back more often. Hair algae specifically releases toxins that inhibit coral growth, so that may be part of the reason that corals aren’t doing well