Step sludge and residue with a sludge judge to confirm pumping need

https://kilo-wiki.win/index.php/Septic_Tank_Pumping_as_well_as_Upkeep:_A_Homeowner%27s_Step-by-Step_Manual

Measure sludge and residue with a sludge judge to confirm pumping requirement, then mix contents gently to suspend solids so the vacuum truck gets rid of both layers, avoiding blockages and premature refilling.