Toilet bubbles.

I have never seen this before, when the bath vanity sink water is running, bubbles come up through the toilet. What would cause this? Toilet also has a slow flush.

Various potential reasons: http://diy.stackexchange.com/questions/13321/what-could-cause-bubbling-toilet-when-the-shower-or-sink-is-running

Thanks Larry, makes sense with the scenario in this case. :wink:

Sounds logical. Some graphics would have been nice though.