Pseudofeces

Bivalves which exhibit this behavior are numerous and include Ostreidae oysters (such as Crassostrea) and Dreissenidae false mussels (such as Dreissena).

Gastropods which filter feed are in a minority, but include the mudsnail genus Batillaria[1] and deep sea vent limpets in the family Lepetodrilidae.

The inner pair of palps transfers smaller and lighter particles, such as phytoplankton, to the mouth, using ciliary currents.

Bivalves can filter the particulate pollutants, and either eat them or discharge them as pseudofeces deposits onto the benthic substrate, where they are then relatively harmless.

Chesapeake Bay's once-flourishing oyster populations historically filtered the estuary's entire water volume of excess nutrients every three or four days.