A
raw culture was prepared with diatoms of the genus Nitzschia and
Pinnularia. Small epiphytic diatoms (Amphora pediculus or Cocconeis pediculus) came
into the culture together with Nitzschia and proliferated strongly.
They grew attached to the substrate and the diatoms of the genus
Nitzschia but not on Pinnularia. The latter can be easily transferred
from the raw culture to a new culture. The following video (120x time
lapse) shows the culture at different magnification levels.