Urbanization and high nutrient loading from anthropogenic activities can saturate biological demand in streams, leading to eutrophication. Freshwater mussels (FWM) can assimilate, transform, and remove excess nutrients via biofiltration, biological storage, and enhancement of sediment microbial activity. FWM cohabit with macroinvertebrates, who also influence nutrient fluxes through functional feeding (FFG) and bioturbation, making them attractive organisms for best management practices. While mussels and macroinvertebrates independently influence stream chemistry, there is potential for synergistic interactions. The nutrient-rich biodeposition and gas exchange conditions of mussels beds could enhance the capacity for burrowing detritivores to influence environmental conditions which promote microbial nutrient transformations like denitrification. This study aims to evaluate how macroinvertebrate and FWM interactions alter dissolved nutrient and gas fluxes and if there is a synergistic effect on nitrogen removal. We hypothesized that 1) mussel-macroinvertebrate cores will exhibit greater dissolved oxygen (DO) loss due to combined respiration of organisms and bioturbation-enhanced O2 respiration in sediment, 2) combined mussels and macroinvertebrates will show greater net effluxes of dissolved nitrogen and phosphorus solutes via bioturbation-facilitated mineralization, and 3) synergistic mussel-macroinvertebrate interactions will increase denitrification. To test these hypotheses, we conducted an in-situ core experiment using 10 cores across three treatments: macroinvertebrates only, mussels and macroinvertebrates, and a sediment-only control. Utilizing Elliptio complanata and a representative macroinvertebrate assemblage, we measured changes in dissolved nutrients (NO3-, NO2-, NH4+, SRP) and gases (O2, N2) before and after 50% DO reduction was reached. Preliminary analyses indicated that macroinvertebrates influence SRP and ammonia (NH3) exchange, with invertebrate cores increased to ~0.005 mg/L SRP more and ~0.025 less N/L as NH3 than the control, supporting the need to investigate their role in multi-species nutrient dynamics. Invertebrate cores had ~41% ammonia and ~72% nitrate concentration of the mussel and macroinvertebrate cores. Knowing that insect macroinvertebrates have a significant signal, we will conduct further laboratory experiments with a mussel-only group. Results from this project will quantify whether potential synergistic effects between mussels and macroinvertebrates on nutrient cycling, informing their capacity to improve water quality in FWM streams.