Hair alge is one of those things that varies from person to person. I know I have battled it over the past year in my 125gl reef and all my perameters are optimal. You will get tons of advise on how to control it and reasons for having it, and most of the time they will not get anything but open ended questions like how new is your tank? What is your lighting? what are you measurements? Whats in the tank? I have heard them all and I also have kept my tank in check (Nitrate-0, Phosphate-0, Silicates-0, Alk-5mel/l, PH-8.3, cal-450), and I still have hair alge. I have tried all the cures and have finally desided to just use the old tooth brush and keep the perameters optimal. Your lighting times seem fine to me and like me your keeping you perameters at a good level so good luck in you struggle with this pest