Usually in the un-sewered rural and urban areas a septic tank is what people use as primary sedimentation tank with large detention time. The water is very important detail for perfect functioning of the tank and there are more details that are crucial about the septic tank. First, capacity of the tank depends of the number of users and interval of sludge removal. Dimensions, detention period, inlet and outlet pipes, baffle walls of the tank, roofing slab, ventilation pipe and more info’s in the link bellow.

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