When the sample is brought into the laboratory, it is often necessary to concentrate the organisms in a relatively small volume of water. For this purpose, the water may partly be filtered rapidly through a fine milling cloth and the residure quickly poured back into a suitable container before filtration is completed.
Biofilm scoured from media put in a container, and then a small volume of water is poured on it. The sample is collected, and a ample air space is left in the bottle (at least 1/2 volume) to supply oxygen. The container should be kept at about 10 degrees C.
We are pipeting free-living organisms under a binocular dissecting microscope (magnification: x10 ~ x20), and begin separate cultures.