Foaming 

PROBLEM: A prolonged foam build-up which accumulates in the corners of the pool or bubbles which remain on the water’s surface for more than a few seconds.
SOLUTION: Apply algaecides according to use directions.  Carefully measure and accurately calculate your pool's volume.  Wash and rinse deck areas carefully so cleaning compounds do not get into the pool.  Use only prescribed surface cleaners on your tiles and pool’s interior surfaces.  Calicum Hypochlorite and Lithium Hypochlorite will destroy organic contaminants, a possible source of foaming. Use 60% Algaecide in pools with attached spas or fountains.