WG, need to pick your mind again,first time owning home with septic system. I had new system installed when moving in about year ago.state involved to meet code requirements ETC. Has 500 gal tank, If I remember right 70' drain field, no lift station needed. Have two bathrooms in home. Lower level & 2nd floor. The lower level is built into hill and floor level is parallel with outside. Anyways last couple days have noticed the water closet on the lower level has been?? gurgling for few seconds or so, like air bubbling and belching back into bowl? Able to hear last night again while in same area of bathroom. Also now noticed (not each test flush) that closet flushes slower and tends to rise and reseed slowly, like when plugged? Not doing in 2nd floor bath. Stand corrected been 1&1/2 years installed just before moving. Havent had pumped nor have I had anyone out to do any servicing since installed. Going to check, mention made some type filter out there. Any ideas welcome! Thanks Mu

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