Customer is having drain issues at there kitchen sink, I filled the right side of the sink and drained it. The left side of the sink filled up and the water drained very slowly, this tells me they have debris coating the sewer line so a conventional snake will not clean the line. I left options to clean the line with chain snake or hydro-Jett, and a possible Bio Clean to keep up on maintenance. The customer will contact us when they decide what they want to do.