This is a simple question. When the upstairs toilet is flushed, the downstairs toilet bubbles up. I realize there is a block somewhere. Can I pour anything into the toilet that may help to clear this up ? I have a septic tank.

Hi Alice.

I doubt that you can clear this up by just pouring anything into the drain line... septic or not.

Tell me, when was last time septic was pumped? What state do you live in? How much snow if any lately?

Hi Alice.

I doubt that you can clear this up by just pouring anything into the drain line...septic or not.

Tell me, when was last time septic was pumped? What state do you live in? How much snow if any lately?
I live in Maryland , on a creek , near the Chesapeake Bay. No snow. The septic was pumped after Hurricane Isabel pushed everything up and into the house . 3 years ago. There are only 2 of us living here and we get it pumped about every 5 years.

This is a simple question. When the upstairs toilet is flushed, the downstairs toilet bubbles up. I realize there is a block somewhere. Can I pour anything into the toilet that may help to clear this up ? I have a septic tank.
There's nothing you can pour into a toilet that will ever take the place of snaking a drain line. That said, back pressure makes a toilet bubble and back pressure's caused by the discharge hitting a partial blocking and bouncing back sending a bubble of sewer gas ahead of it. The solution is to snake out the line. But first you have to determine which line to snake. Open up the house cleanout to the septic tank and cycle the washer. Did the line fill up when the washer pump kicked on? Yes? Then check the septic tank and the line from the house. NO? Then the blockage's inside and you must snake from the downstairs lavatory roof vent or you could pull the downstairs toilet and snake from the open closet bend. Good luck, Tom