Partial Recirculating Aquaculture Systems (PRAS) are designed to recirculate up to 75% of the water without the need for biofiltration, which provides some critical advantages to aquaculture compared to full RAS. IAS supplied the complete PRAS equipment package along with comprehensive on-site startup, commissioning and staff training services for a USF&W salmon and steelhead fish hatchery in Washington state. The PRAS equipment supplied by IAS includes Pentair Berkeley and Aurora vertical line shaft turbine pumps to meet the engineered duty points with best efficiency (BEP). Amiad inline & HEX X-series drum filters were supplied to provide automatic self-cleaning solids filtration. Disinfection is handled with SITA model 400 series UV sterilizers with state-of-the-art TC control panels to provide a up to 300 mJ/cm2 UV dose. Aeration is provided by regenerative blowers delivering air to culture tanks through efficient disc diffusers.