i recently had a nasty waste pipe clog in the floor. i had to call a sewer service to handle it. thank the heavens they're out there. i know things like this don't happen over night. i'm just wondering if there is a simple periodic maintenance i can do to avoid this in the future. does anyone know of something i can pour into the pipe to help keep it clear? i'd like to keep it earth friendly, if possible. thank you, gene m.