Septic tanks are designed to be an underground chamber or container that domestic wastewater will flow for basic treatment. A septic tank system is also considered to be a simple onsite sewage facility ideal for rural areas where municipal treatment facilities are not available or are cost prohibitive. National Storage Tank carries the award winning Snyder NexGen single and double compartment septic tanks. With sizes from 750 up to 1500 gallons which are the ideal size for most any residential application. The NexGen septic tanks are durable with a superior structural design, a one piece tank without any seams to leak and manufactured using a rotational molded process.