The article is dedicated to Pavel A. Stunzhas, a highly qualified specialist in the field of Marine Hydrochemistry, a graduate from the Moscow Institute of Physics and Technology. He was a Senior Researcher at the Laboratory of Biohydrochemistry at the Shirshov Institute of Oceanology Russian Academy of Sciences, PhD on Physics and Mathematics sciences. July 2, 2020, he celebrated his 80th birthday, but by the will of fate and COVD'19, he suddenly passed away on October 29 of this year. He worked at the Institute of Oceanology for 46 years – from the first to the last days of his life.