This is a protocol from: Suttle, C. A. and J. A. Fuhrman. 2010. Chapter 15: Enumeration of virus particles in aquatic or sediment samples by epifluorescence microscopy. Manual of Aquatic Viral Ecology. Waco, TX:American Society of Limnology and Oceanography. doi:10.4319/mave.2010.978-0-9845591-0-7Please see the published manuscript for additional information.