Summarize the following:
Use your brush to clean the bottom and sides of the pool again, then vacuum up all the dead algae. If there are a lot of dead particles and you're having trouble vacuuming them, you can add a flocculent to help the algae bind together and make it easier to vacuum. Your swimming pool water should be crystal clear after treatment. If the algae seems to be coming back, go through the shocking and treating process again until it's all cleared away. All chemical levels should be in the normal range.
Vacuum up the dead algae left behind in your swimming pool. Run the filter until the algae is gone. Re-check chemical levels with your swimming pool test kit.