Our septic pumps uphill from the house to the distribution box at the leach field. It is then supposed to flow in to 4 pipes that feed in to the septic drain field chambers. However, one of the pipes is slow to drain and will backflow into the distribution box. When the level gets high enough, it drains into the other 3 pipes. I figured the blockage was either biomat or roots. I didn't want to do this job. I called many septic and drain cleaning companies so I could pay someone else to do it. The drain cleaning services wouldn't hydro-jet or use a drain auger on a leach field and the septic services just wanted to dig it up for thousands of dollars. See the links below for the parts and tools I used:
Roebic Foaming Root Killer:
https://amzn.to/3jlPgwh (affiliate*)
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