I am sure there are some qualified people on here to answer this, so I figured I would take a shot. I have a slow bathroom drain that has been slow on and off for a while. Plumbers have cleared it before, but it seems like the blockage is down in the pipes at least a few feet. It got slow again and my landlord is suggesting trying Draino/Liquid Plumber, but would this help at all given the blockage is down low? I took apart the fixture under the sink and cleaned out the pipes fairly thoroughly, but it seems the problem is deeper in the pipes. Suggestions without calling a plumber?