On December 4, 2019, teams of Institute of Marine Biology of the National Academy of Sciences of Ukraine (Odessa) and A. O. Kovalevsky Institute of Biology of the Southern Seas of Russian Academy of Sciences (Sevastopol) suffered a painful and irreparable double loss: Director of IMB D. Sc., Prof. Boris Alexandrov and senior scientist, PhD Galina Ivanovich tragically perished in a terrible fire in the building of Odessa IMB. Boris Alexandrov was a talented scientist in marine ecology, widely-known expert in international hydrobiological community, as well as an outstanding teacher and respectful leader of a large Institute’s staff. Boris Alexandrov lived a remarkable and active life of only 61 years. List of his scientific merits and achievements is impressive: Doctor of Biological Sciences, Professor, Corresponding Member of NAS of Ukraine, laureate of the State Prize for Science and Technology of Ukraine, Honoured Worker of Science and Techniques of Ukraine, author of the more than 200 scientific papers and monographs. For more than 10 years, Boris Alexandrov was the Head of the Biodiversity Conservation Expert Group in the Black Sea Commission for protection of the marine ecosystems against pollution. Galina Ivanovich was expert in physiology of marine organisms. Since the beginning of her research career (1985), she worked at Odessa IMB, and published more than 50 scientific articles. The blessed memory of Boris Alexandrov and Galina Ivanovich will forever remain in our hearts.