Mathematical models play a crucial role in bivalve aquaculture research, facilitating predictions and optimization of coastal aquaculture. These models can vary in the complexity of simulated processes and can be applied at different spatial and temporal scales and resolutions, which have implications for the potential research question to be addressed and for the computational power required to run simulations. This study examined the performance of ecosystem and farm-scale models in simulating bivalve growth and farm productivity, focusing on the effects of spatial and temporal resolution under a range of environmental conditions in Hardangerfjord , Norway. The study relies on two previously published models: an ecosystem model, NORWECOM.E2E, which has been recently coupled to a Dynamic Energy Budget (DEB) to simulate the bioenergetics of mussels, and a farm model that simulates the effect of the suspended canopy on local hydrodynamics to predict mussel growth using DEB theory. A series of numerical experiments revealed that the characterization of water currents in relation to the orientation of the farm is challenging and can lead to uncertainty in farm-scale models. Further, the discrepancies between modelling approaches were strongly dependent on the stocked biomass, with low biomass scenarios minimizing these discrepancies. Based on the results, the NORWECOM.E2E-DEB ecosystem model can be used to explore site selection and aquaculture environment interactions without impacting the estimations of farm production predicted by the farm-scale model to a critical level. The study underscores the potential of combining both modelling approaches for holistic coastal and farm management, providing valuable insights for future aquaculture development.