Kitchen drain has decided to be slow. Might be from junk from the dishwasher, not sure what. I checked the trap, it was fine. Went to the first clean out is could access, and very carefully cracked. Yep, standing water. That pipe is about 15 foot long so I'm in no hurry to drain it! I can feel the temp in the PVC pipe change as I follow it down, and it appears to be clogged before the next available clean out. Go figure. Since it drains, but slowly, and I suspect the clog in a bad spot in a bad spot, might this bio clean stuff work? All my pipes are PVC, and I don't want anything bad for the septic tank. Everything else in the house drains ok, just not this sink.