sounds more like briopsis.
Do the strands look like little ferns?
What test kits are you using for N and P? Cant really be ) or you would not have this stuff growing.
While we can get the algae to go away, we need to make sure we get the nutrient issue under control, or it or something else will just come back.
So, how big is your tank, whats tour livestock, how often and how much do you feed, and what are you doing / running for nutrient export?