Permeable sandy sediments play essential roles in the coastal ocean's organic matter (OM) turnover and nutrient cycling. Here we collected the North Sea sands around the island of Sylt, Germany (August 2020), and incubated them using flow-through reactors to investigate the biogeochemical processes during the transition of redox conditions. This dataset included the changes of major parameters (O2, Mn, Fe, P, SO42-, NH4+, NO3-, DIC, pH, etc.) during the anoxic incubation of these sands. This is a supplemental dataset for the following peer-reviewed publication (doi.org/10.1016/j.scitotenv.2022.161168).