Baffled: Why no back up in bath tub?

[coyote]

The toilet was backed up full and not flushing. I opened a cleanout in the main drain where it enters the septic tank; found the pipe was full of water. I cleared a clog at the entrance to the tank, the water gushed into the tank, and the toilet now flushes fine. What I don't get is why water didn't back up into the bath tub, too, since its drain is lower than the rim of the toilet. Any ideas? Thank you!

 

[Reach4]

Some houses have two inputs to the septic tank.

Also, there might have been two clogs. The one you cleared, and the one near the toilet that broke loose when you cleared the downstream clog.

 

[Sponsor]

 

[hj]

Once the water reached the TOP of the riser int the toilet, the toilet would no longer flush, but the bathtub drain is usually higher than that. You just didn't use enough water to flood it.

 

[coyote]

Some houses have two inputs to the septic tank.

Also, there might have been two clogs. The one you cleared, and the one near the toilet that broke loose when you cleared the downstream clog.

Yes that makes sense--the lower clog caused a back up in the pipe which caused another clog in the toilet, allowing water to reach a level higher than the tub. Thanks!