Septic System Safe Laundry Detergents - The Spruce
The type of septic system you use will determine which type of laundry detergent is the safest to use. For a conventional, gravity-powered system, use a liquid form of laundry detergents. However, for an aerated septic system, you can use either liquid high-efficiency (he) or powdered laundry detergent to avoid excessive foam in the aeration ...