ABSTRACT
This chapter discusses the use of a generalized microbial film fermenter capable of operating under quasi-steady-state conditions. The importance of microbial film and its complexity as an ecosystem make it a most interesting area for ecological study. This very complexity makes in situ investigation extremely difficult, suggesting that laboratory model systems are needed if the fundamental processes of microbial film are to be understood. The constant-depth film fermenter maintains a steady-state by physically removing growth once a predetermined depth of film has been generated. A variety of surfaces may become colonized by microbial film, and characteristic properties of a given film may be determined by the nature of the substratum material. Microbial films are responsible for so much economic damage that a brief discussion of economic applications of film fermenters seems important. The resulting microbial film is a complex heterogeneous ecosystem with bacteria held in a matrix of polymeric substances produced by one or more of the species involved.
