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My husband and I bought a house in July. During the home inspection, water was run for upwards of 20 minutes with no issues noted. When we moved in August 1st, we instantly noticed issues with the plumbing, such as gurgling in the toilet when the water ran in the shower. We had someone come drain the septic tank and they cleared the drainline as well. About a month later, we had similar issues, so my husband snaked the toilet out 100 ft finding nothing, and we used a drain cleaner. That seemed to work. Now, we're having trouble AGAIN. Same problem: bubbling in toilet when water is drained elsewhere, gurgling in pipes when toilet is flushed. What else can we do? My husband thinks it may be the toilet itself, because it has always been slow flushing. Thoughts?