I pumped my septic at 10 years 3 times in my house, always looked good when the lid came off.
My rental house was having issues getting backed up and needing emergency pumps that adds a few $$$.
l was down there a few years ago and did an inspection and found the out pipe tipped up, had that repaired and new filter installed.
Inspection/ filter cleaning earlier this year it didn't look great but was ok, few inches scum/ solid layer, broke it up with a shovel.
Tank additives IMO do nothing , renter was using them monthly .
My rental house was having issues getting backed up and needing emergency pumps that adds a few $$$.
l was down there a few years ago and did an inspection and found the out pipe tipped up, had that repaired and new filter installed.
Inspection/ filter cleaning earlier this year it didn't look great but was ok, few inches scum/ solid layer, broke it up with a shovel.
Tank additives IMO do nothing , renter was using them monthly .