You Have Found The Satan...!
Characteristics : Short, irregularly - bent filaments, 0.8 micron in diameter and 50 micron in length, found
extending from the floc surface and free in the bulk solution. No sheath and no attached growth. Cells are oval - shaped
rods (0.8 x 1.5 micron), and appear as a "chain of cells", with indentations at the septa. Gram negative and Neisser
negative; Neisser positive granules may occur. No sulfur granules.
Identification : Relatively short, non-motile filaments (10-50 µm). Irregularly bent filaments with no branching.
The filaments sometimes coil giving it the appearance of almost being branched. Cells are oval-shaped rods
(0.8-1.2 x 1.5 µm) and lack a rigid trichome. There are indentations at the septa. Filaments are found extending from the
floc surface and free in the bulk solution. The filament staining is Gram negative and Neisser negative. Neisser positive
granules may occur. Usually easy to identify due to its appearance as a ‘chain of sausage-like cells’. No sulfur granules.
Usually no attached growth. No sheath. This filament occasionally is observed as a cause of foaming. Typically when there
is a high F/M ratio or at MCRT’s of less than 2 days. The foam is usually white-grey and is easily collapsed.
Similar Organisms : Bacillus is similar although is stains Gram positive.
Environment : This filament is usually found in environments where there is a low DO. It can also be found after
RAS Chlorination. Foaming can be found when high F/M conditions with low MCRT conditions exist.
Control : F/M can be changed by increased sludge wasting, changing from complete mix to plug flow or use of a
selector.
Rank : 1863 is not found on most charts being ranked at less than 19 or more.
