4spdragtop, when the tank is completely full after a hard rain and wife decides to take a shower, or run the washer machine, the toilets will start having bubbles of air escaping, within 5-10 the water backs up in the shower. Now the toilets have always made a weird gurgling sound when flushing, even if we haven’t had rain in a while. Which is why I thought maybe my roof vents where clogged up as well. I have two bath rms with a vent stack in each. Master bath has a 3” and the other bath 2” venting up through the roof. The county inspector will be here at 1:30. I’ll see what he has to say and take it from there. I might just dig up the lids later and take a measurement so I can order the risers for starters that will at least eliminate that point as an intrusion point. I had the tank pumped July 18’ then it backed up again a few times, I found the discharge pipe leaking fixed that in may 19’. Now I‘m here again back to square one. I’m trying to eliminate all the variables. I’m going to figure this out eventually, God willing.
