Green water on La Ropa

My wife and I just returned from a swim at the west end of La Ropa by the rocks. Been swimming there for last 10 years, an always found the water to be crystal clear and delightful....today not so much. Water had abundant green bubbles and a equally green tint. Plus, alot of floating plastic....more than usual. Bummed us out...thought La Ropa is a politically designated "Blue Beach"! WTF?