I have had some recent trouble with my 55 growing hair algae. What I done to help was buy a tooth brush. I scrub it all off the rocks while they are in the tank being careful not to hurt the corals but also brushing it off them. I then did a water change and waited about 2 hours and then cleaned off all the screens on power heads and pumps. I did this every other day for 1 week now I only scrub the rocks once every week. before i change the water. I use ro water have done nothing different or added any corals and this stuff just popped up one day and I let it go until it took over. It took 2 hours the first time 1 hour the next and it took 20 min. on Monday the tank looks real good today. I know you will still want to check your phosphates and nitrates. Maybe cut the lights down to 8-9 hours a day. good luck