Look like hair algae, were are you nitrates and phosphates? defiantly aptasia get a matted file fish for the aptasia and once you know what you nitrates and phosphates are the you can attack the green algae
File fish eat acans how many times do have to remind people. I keep three small damsels in a 90 gallon tank I don't have nitrates or phosphate. I feed twice a day only what they eat.