New room, old plumbing, bubbles
We recently added a laundry room to our main floor. Originally it was drained in to a tile line to the great outdoors, now it drains into the septic system. We have two toilets, two sinks, a shower stall, a bathtub and the washer all draining in to the septic line within a few feet of each other. When the washer empties, one of the toilets bubbles. The one that doesn't bubble, is a new low flow toilet installed at the same time as the washer. I have also noted on occasion that the water level in the older toilet is lower than normal. I also learned pretty quick not to flush that toilet when the washer is emptying. I have not checked the septic tank, we have a couple feet of snow on top of it, thought I would see if it is something else first. Thanks