Procedure sludge and scum with a sludge judge to validate pumping need

https://smart-wiki.win/index.php/Septic_System_Pumping_and_Maintenance:_An_Individual%27s_Step-by-Step_Quick_guide

Step sludge and residue with a sludge judge to verify pumping requirement, then blend contents gently to suspend solids so the vacuum truck removes both layers, avoiding clogs and early refilling.