Part 1 of Essay
Red tides also known as harmful algal blooms, HAB for short, are a toxic, single celled algae called photoplankton. This organism produces a toxin that affects the central nervous system of fish so that they are paralyzed and can't breathe. As a result, red tide blooms often result in dead fish washing up on beaches. ....

Part 2 of Essay
.... in the color of the water at all. This makes a red tide very hard to predict or find. Red tides often occur when fresh water runoff creates a stratified surface layer above colder nutrient-rich waters. "heavy rains might have helped the red tides develop by pouring fresh water and nutrients into surrounding sea waters," (New York Times: Sept. 19, 1996) Fast growing algae quickly strip away nutrients in the upper layer, leaving nitrogen and phosphorus only below the interface of the layers, called the pycnoclin ....