I found two great books at NCSU library last night.
Detection methods for algae, protozoa and helminths in fresh and drinking water. Chichester, West Sussex, England: , 2002.
Cyanobacterial state of the science and research needs. Vol. 619. New York: Springer, 2008.
Cyanobacteria is really not a true algae, but acts like one and is commonly referred to as blue-green algae. There are surveys suggesting that half of the Cyanobacteria blooms are toxic. This creates a lot of concern should blooms form in reservoirs that are used for drinking water. Cyanobacteria also can have a negative impact on odor and taste in drinking water. Musty, earthy and stale are common descriptions of these odors and tastes. Efforts are being made to reliably detect the presence of Cyanobacteria as well as associated toxins.
One of the books also refers to this flowcam, for remote analysis of water particles:
There is a bench model and a portable model.