You need to find the cause and end it. Ill bet you its one (or a combo) of various things.
2)Bad lighting/too much lighting
How much do you feed your fish? What do you feed them? How often?
How old are your bulbs? What kind of bulbs? How long are they on? Is sunlight, room light, able to get into your tank?
When do you do PWC
and how much?
water for top offs and PWCs?
The hair algae needs nutrients and light to grow. If you cut them both back, the hair will die. How high are your phosphates and nitrates? Since I cant avoid phosphates due to feeding, I run GFO
and am starting up some chaeto to take over once the GFO
needs replacing. My water is much clearer and I have much less algae in it now.