AbstractThe objective was to design and evaluate a suspension oyster tray unit to optimize conditions necessary for the successful commercial culture of Pacific oysters for the half‐shell trade.Units were located at two sites in Trevenen Bay. One location was sheltered and calm; the other was a natural tidal raceway with intense current flow. The purpose was to test the ability of the design to provide uniform growth, retard fouling, be handled efficiently and be economically feasible to construct. Assessing performance was based on monitoring shell growth, condition index, fouling occurrence, materials handling and the capital costs of the system. Field experimentation began in June and terminated in October 1979. Suspension tray units performed similarly at both sites, exhibited little variation in shell growth in the series of five trays in an assembly, retarded fouling and proved economically feasible for commercial us