Answer

My pool went green! What do I do?

Algae are the microscopic aquatic plants that are constantly being introduced into the pool water from the atmosphere. If not kept under control, algae can discolor your pool water, clog your filter, cause unpleasant odors and produce slimy, slippery walls and floor. Algae growth is common when the disinfectant level, or algaecide content, in the water is low or neglected.
Algae are not something we want to see in swimming pools. If we maintain proper water balance and adequate sanitizer and algaecide levels we should never even see it.
However life is busy and sometimes it sneaks up on us and takes over the swimming pool.
There are two things we need to do when algae appears.
 
1. KILL IT
1 Balance the water
2 Super chlorinate the pool (raise the pool to ten ppm)
3 Add BIOGUARD Erase to the pool the next morning
4 DO NOT let the chorine levels fall to below 3 ppm. Remember Chlorine demand is high when algae are present. Chlorine can disappear quickly. You might need to add chlorine 2 or 3 times a day until the pool is clean.
5  If its green it is not dead.
 
2. CATCH IT
1    The filtration system should be run continuously. If you turn your pool off at night time it will take twice as long to control the algae bloom.
2  The pool surface should be brushed  daily. This will remove dead layers of algae and allow the chemicals to combat the remaining layers of algae growth.
3 Watch the pressure gauge on the filter and backwash or clean it when necessary.
4 Dead algae make the water look cloudy and the particles can be quite small. If your pool uses a sand filter it will need help (a clarifier) to catch these small particles.