Clorox on Black Algea

[leigh]

I have tried the black algea shocks/treatments and still have the black in spots on the side of my concrete pool. I have been told that the algea "implants" itself and is very hard to kill...we also have a hot tub that flows into the pool..I tried draining it and spraying Clorox on it and it killed the algea and no return. What I need to know, will I damage the pool if I drain the water down 3-4ft, and they spray the concrete with Clorox?

[Algea Helper]

Draining some water and treating with liquid chlorine would not create any problems. It will destroy any algea that has implanted itself into the surfaces you treat.