A removable filter on the tank's outlet that catches solids before they enter the drain field. Modern Ohio installs include them; older tanks can be retrofitted. Annual cleaning is a 5-minute job that adds years of drain field life.
More detail
Effluent filters (Polylok PL-122, Zabel A300, Sim/Tech) are mesh or perforated screens that fit into the outlet baffle and catch solids before they reach the drain field. Modern Ohio installations almost always include one; pre-2000 installations typically do not. Retrofit cost is $150-$250 including the filter and 30 minutes of labor during a routine pump-out. Annual cleaning is a 5-minute job: lift the filter out (long handle for service), rinse with garden hose, drop back in. Cleaning saves the drain field by preventing solid escape that accelerates biomat formation. Cincinnati we typically include a free filter cleaning during scheduled pump visits if a filter is installed. Homeowners can clean filters themselves if comfortable opening the outlet riser, or have it done as part of routine service. Cincinnati effluent-filter retrofit pricing: $150-$250 for the filter and 30 minutes of labor during a routine pump-out. Annual cleaning is a homeowner-doable 5-minute job: lift, rinse with garden hose, drop back in. We include free filter cleaning during scheduled pump visits if a filter is installed. The filter saves the drain field by preventing solid escape that would otherwise accelerate biomat formation.