During two crusies in June (AL510) and September (AL516) 2018, a data set (N=76) from the sea surface microlayer (SML) was compiled in Eckernförde Bay, Germany. SML samples were collected with the glass plate technique. Reference samples from the underlying water (ULW) at an approx. depth of 20cm were collected with the help of a bottle. Total and dissolved hydrolysable amino acids, combined carbohydrates and dissolved organic carbon were analyzed to describe surfactant dynamics (based on phase-sensitive AC voltammetry). Flow cytometry provided additional information on bacteria and phytoplankton community composition. This data set resolves dynamics on short temporal (diurnal sampling ) and local scales (within an area of 50km^2).