How to clean out sewer main line problem.
The plumber has been here 4 times in last month. He is doing his job, and he got out a small amount of tree root. He thinks that the old cast iron pipe might be 'scaling' and stuff is getting caught on that. Will regular doses of some good drain cleaner help? If it starts to back up in the floor drain 'hole', I generally wait 1/2 hour and then flush or wash another load of laundry. We rented the house for 2 years and then bought it recently. Had to have this service once during rental. It seems to have magnified for some reason now.