1500/500 Siphon Tank – Suitable for 4-5 bedrooms, these tanks are configured for low pressure dosing (siphon) systems. Ideal for sustainable pressure dose septic systems, where applicable, as they do not require power to operate and have no mechanical moving parts to maintain. A minimum elevation drop is required between the tank outlet and the drain field, contact Glacier Precast to determine if this system will work for you. Traffic rated drive-over lids and castings are available as an option along with concrete, PVC or fiberglass risers and lids.