Scottturner is right--chlorine of 2-3 isn't going to be enough to kill an algae outbreak, no matter what your CYA level, and may not even be enough to prevent an outbreak if you started with clear water. If you'll please post your current CYA level as well as what type of pool you have, it will help us give you a target chlorine level to kill the algae, which will have to be done before there's any hope of getting it out of the pool. This is going to require raising your chlorine to shock levels, and KEEPING IT RAISED, even if it means testing and adding more chlorine 2-3 times daily. When the algae dies, it will turn grayish, then you can concentrate on getting it out of the pool.

Janet