Microthrix parvicella Gram 1000x
Microthrix parvicella Kristallviolett 100X
Microthrix Parvicella Lebendpräparat 100X
Microthrix parvicella Neisser 1000X
Microthrix parvicella
One of the main causes of scum and bulking sludge.
Morphology:
| Filament position: | inside and outside flakes |
| Branching: | none |
| Movement: | none |
| Growth habit: | severely bent to entangled |
| Aufwuchs: | absent |
| Constrictions: | barely visible |
| Sheath: | absent |
| Transverse walls: | not identifiable |
| Cell form: | not identifiable |
| Length of filaments: | 200 – 400 µm |
| Filament diameter: | 0.5 – 0.8 µm |
| Gram staining: | positive dark blue |
| Neisser staining: | positive dark polyphosphate granules |
Factors promoting growth:
- low to medium sludge load (0.05 – 0.2 kg BSB5 / kg TS * d)
- temperature < 15 °C
- long-chain fatty acids in inflow
- requires ammonium as source of nitrogen
- Bio-P and denitrification benefit growth compared to flocculants
Countermeasures:
- dosage with aluminium sulphate or SACHTOPUR (approx. 2 g Al/kg TS * d)
- increasing sludge load
- improving fat separation
- reducing nitrification level
- decommissioning Bio-P stage in winter