Sewage pump are pumps used to remove waste water that contains solids up to 2 inches in diameter.
The most common appication for draining bathroom water water to sewer or septic line.
Effluent pumps are pumps used to remove gray water from septic tanks, sump pits or laundry tray system.
Gray water is waster water from bathtubs, sinks, washing macihnes, and other kichen appliances.