Not all septic systems have an effluent filter. An effluent filter is only installed as part of a septic design plan housed inside your outlet baffle. Should your system have an effluent filter it requires regular maintenance. At a minimum, the filter should be cleaned whenever the tank is pumped, sometimes more often. Failure to clean the filter can lead to slow drainage, clogged pipes, and backups at the septic tank or even inside of your home.