Schematic diagram of the experimental set up and analytical process used in this study, broken down into six steps. 1) Aliquoting of three independent surface sediment grabs, 2) Addition of DNA treatments, 3) Chilling samples in sets of 3 reps × 13 time points (or 14 time points for control samples, which include a time 0 control), 4) The storage phase where triplicates of each treatment are removed from fridge at specific intervals and frozen for later analysis, 5) DNA extraction of all treatments including controls, using a QiaCube (QIAGEN, Germany), 6) DNA amplification of N. spumigina-spiked treatments and a specific investigation of Microcystis abundance via droplet digital PCR (ddPCR) and metabarcoding of the non-spiked control samples for assessing community structure.