Have you ever noticed schools of dead fish floating or seen blue-green scums that coat the surface of Clear Lake in the summer and fall? These are common signs of poor water quality caused by excessive nutrients such as nitrogen and phosphorus. Like fertilizer for your lawn, nutrients help algae grow. This is important because algae provides most of the food available in lakes—eventually making its way up the food chain to the bass that people like to catch—however, too many nutrients can cause harm.