Green Hair Algae - Will not go away!

[oyf709]

Do you have any direct sunlight can reach the tank at all? That could promo hair algea growth.

I used to have the similar problem until some guy told me to move all coral to a QT tank and keep the main tank running without any light for 3 months, I end up solved the issue that way. However, you will have a big enough QT tank and also have te time to keep up the water quality in the QT tank.