The FUMSECK cruise was a one-week technological cruise, which took place in spring 2019, in the gulf of Genoa (NW Mediterranean Sea), onboard the R/V T´ethys II. Its aim was to perform several technological tests of some instruments used for the study of the fine-scale processes and dynamics. It was conducted in preparation of the BioSWOT-Med cruise in the SW Mediterranean Sea in 2022, planned as part of the “Adopt a Cross Over” initiative organising simultaneous oceanographic cruises around the world during the SWOT fast sampling phase. During FUMSECK we tested various technological innovations for the study of fine-scale dynamics and their coupling with biogeochemistry.