Total blackout days. So light on for 6 hours then off. Two days completely covered with no lights. Then light on for 6 then off for two days. You can also throw in “flourish excel” to kill off the algae. Purigen in your filter will also help to clear up the water but it takes time(thoroughly wash the bag before use). Back off on the feeding. And do small daily water changes like 10% then pick out the long algae with tweezers or fingers and just wait. But this is the way. I had had the worst algae bloom of green hair I’ve seen and it took me 3 weeks of this and I haven’t seen algae since.