A septic filter, often called an effluent filter, is a device installed within the septic tank, usually at the outlet pipe. Its primary function is to trap and filter out solids and debris before the effluent (wastewater) exits the tank and flows into the drain field. By doing so, it protects the drain field from clogging and extends the life of your septic system.

A septic system is an underground wastewater treatment structure, used in rural areas without centralized sewer systems. It consists of a septic tank and a drain field.