About a week ago someone in my house used liquid plumber on a perpetually clogged drain in our bathtub upstairs. It fixed the clog. A few days after that, someone flushed the upstairs toilet and suddenly the downstairs toilet started making a bubbling "glug glug" noise, air bubbles. I soon discovered the downstairs toilet was now clogged but the upstairs was all clear.

I plunged the downstairs toilet until it became unclogged and everything was fine. But about a day later someone flushed the toilet and all of the waste from the upstairs flush quickly backed up into the downstairs toilet and it began to overflow. I quickly unclogged the toilet and again, and again the line was free.

Now, every 1-2 days, the glugging sound returns and the downstairs toilet needs to immediately be "unclogged" or a single flush or shower will overflow the bottom toilet. I tried a snake and it either hit the blockage or the snake didn't hit anything, it's hard to tell, but it seems like this is some kind of partial clog in the drain that probably builds up solids like toilet paper or whatever over a period of a day or two and then becomes clogged again. It's the only thing I can think of. Perhaps the clog that was fixed in the upstairs shower broke loose and went further down the line?

All I know is that we're moving in a few months and I do not want to spend money on a plumber to fix this problem if I can fix it myself. I know it's not advised, but would trying liquid plumber in the downstairs toilet be good as a last resort? or perhaps even in the upstairs tub again to work its way down the drain?

Any thoughts on what this sounds like and how I can fix it? I realize it could be a venting issue but then it seems mighty suspiciously timed with the fixing of the other long-term clog in the tub.

Thanks.

Forget the chemicals. The drain pipe needs to be mechanically cleaned with the properly sized equipment.

Meaning a plumber is my likely only option? Or should I try a new snake?

The partition restriction is in the main line. If you have a cleanout, use that with a larger cable. Otherwise, have someone who knows what they are doing.... a licensed plumber.


Best Wishes