For hydro-jetting, separate the line, install a backflow preventer, start with lower PSI, then increase as needed

https://wiki-neon.win/index.php/Budget-Friendly_Sewage-disposal_Tank_Cleaning:_Specialist_Tips_and_Local_Solutions

For hydro-jetting, isolate the line, install a backflow preventer, start with lower PSI, then increase as required, using suitable nozzles to scour biofilm, roots, and scale without harming pipes.