Limitations
of
Membrane
Filtration - There are certain limitations with the membrane filter method. Samples, which contain large quantities of colloidal materials or suspended solids such as iron, manganese, flocs, clay or algae, can clog the pores and prevent filtration.
If the bacterial counts are high in such cases, a higher sample dilution must be used to minimize the effect of turbidity. Industrial wastewaters may contain zinc, copper or other heavy metallic compounds which adsorb onto the membrane surface and interfere with subsequent bacterial development.
