Best solution is good salt, good water (RODI), and lights in proper time spans, and good filtration. I had hair algae, but after I started making sure my fuge was running properly and working to its potential and whatnot, eventually it went away, and my sump macro was growing by leaps and bounds. Most of the time we have our tanks set up and running before we have a fuge established, and then the powerful tank lights make the display tank act as a fuge instead. Run your fuge light 24/7 for a few days and then reduce DT light at the same time, you'll see it turn around.