My lower level toilet started making bubbling noises when my softner was running. I have a septic tank. The water went down to almost nothing in my toilet, but when I flushed it, it backed up. Later on, I tried and it flushed normal, but is making the bubbling noise again when I did laundry and went down again. I see no visible signs of my septic tank backing up. If it was, I wouldn't think the water in my toilet would go down. Any suggestions?

Thanks

Danny

I think your vent stack is partially blocked. When your softener drains it caused a slight vacuum in the lines a and siphoned water from the toilet. You need to rod the vent, preferably from the roof if you can do that safely.