Manure samples for this study were collected from a commercial dairy farm lagoon located in central Washington, in the Pacific Northwest of the U.S.A. Samples of liquid dairy manures were transported to the lab in 20-L sealable plastic buckets and frozen prior to use for this study. The manure samples were thawed at lab temperatures prior to startup of experiments. The dairy wastewater was screened through a 1.40 mm sieve to remove debris and larger solid particles. This screening was essential to avoid pipet-tip clogging during wastewater sampling and to ensure integrity of samples.