The working principle of this apparatus is that the rural household sewage enters into the concrete pond through the influent pipe,
after which it first enters into the sewage sediment pond for sedimentation, and then overflows from the influent reservoir baffle to penetrate into the substrate layer through the influent channel. This means that,
when it penetrates into the substrate layer from the beneath of the influent sediment pond,
it goes through the substrate filler layer and soil layer from bottom to
top and,
after the filtration process,