As part of the KRYPT-S project, the Leibniz Institute for Baltic Sea Research in Warnemünde (IOW) is procuring an ion chromatograph (IC), commissioning it, and establishing analytical methods for marine and nearshore samples. The goal is to determine key inorganic ions with high precision and reproducibility, particularly sulfate in seawater and sediment samples. This analysis is a crucial prerequisite for calculating gross sulfate reduction rates in combination with ³⁵S incubation experiments and thus investigating cryptic sulfide production in nearshore sands of the German Baltic Sea. The project closes a currently existing analytical gap at the IOW and strengthens the investigation of coupled sulfur, nitrogen, carbon, and phosphorus cycles under oxygen-deprived conditions. The proposed infrastructure thus lays the foundation for characterizing processes that are highly relevant to biodiversity, nutrient release, and the response of coastal ecosystems to hypoxia and redox shifts.