Swimming pools blog

Hello all,
I was wondering what product you would recommend to
get plaster back white again and get rid off all yellow/brown algae on
walls and bottom.
My pool gets really dirty and it looks old but its only 3 years old.
We brush it every week but I was told that only spreads it around.
The chlorine is also kept very high but that doesn’t work.
I want to try to make the pool look like new again. Its very frustrating
seeing all that money we poured into this thing and it look like it does.
Thanks for any help!!!
~rose