To skimm off the top layer from a body of liquid continuously, Suparskim® skimmers must follow the liquid level. For level variations beyond 90 mm, floating skimmers are used.
The floating series 91 skimmers use the same, self-adjusting, skimmer trough, but are also fitted with one or more floats. The floats cause the skimmer to go up and down with the liquid level, the self adjusting trough sees to skimming off the top layer only.