What would you consider your plant density? Light, moderate, or heavy? Also, are you using CO2 or some form of carbon supplementation? How much light are you using?
If this is your first planted tank,
this is an excellent thread to read. Even if this isn't your first tank, it's good to read over as a reminder.
Anyway, cyanobacteria, and the algae that you said was long and probably sways along with the water flow, should be taken care of with a 3 day blackout. I suggest you add to your plant density after the 3 day blackout, add CO2 if you haven't already, and if your tank is about 2.5-3 watts per gallon, cut your photoperiod down to 8-10 hours if it's more than that.