Recently, Scanning Electron Microscopy (SEM) has been used to
further study anaerobic microorganisms and their degradative effect.
SEM permits the observation of spatial distribution and morphology
of bacteria. For instance, external surface of anaerobic
biofilms [7] and internal structure of anaerobic granular sludge
[8] have been previously studied with this technique. However,
to the best of our knowledge no information is available regarding
SEM examination in CSTR anaerobic sludge