What is the purpose of "effluent filters" in a septic tank?

The purpose of effluent filters in a septic tank is primarily to prevent solids from entering the drain field, which is crucial for maintaining the functionality and longevity of the entire septic system. These filters act as a barrier that allows only treated liquid, or effluent, to move from the septic tank into the drain field while trapping undigested solids and scum. This is significant because if solids were to enter the drain field, they could accumulate and create clogs. Such clogs can lead to expensive repairs, system failures, and potential environmental contamination.

In contrast, other options describe functions that effluent filters do not perform. They do not increase the speed of wastewater treatment; the treatment process relies on biological actions within the tank. They also do not aerate the wastewater, as aeration occurs in engineered systems designed for that purpose. Furthermore, they do not monitor chemical compositions; such tasks require different types of equipment for testing and analysis.