This publication relates to a system for pumping particles (2) in a liquid, in particular living fish in water, where a chamber (4) draws a liquid and particles (2) up from a liquid volume (1) through a closed duct (3), the chamber (4) being connected to the suction side of an ejector (7) and a pump (13) for formation of a sub-pressure in the chamber (4).At the same time, gas supplied from the compressor (12) to the liquid column in the chamber (4) contributes further to the acceleration of liquid flow through the chamber. The ejector (7) is driven by a liquid flow from the pump (13) or of gas from the compressor (12). The closed duct (15) is connected to a non-return valve or check valve (14), preventing liquid and particles (2) from returning to the liquid volume (1). Liquid and particles (2) are transferred out of the chamber (4) and through the ejector (7) and then into a closed duct (15) to the receiving unit I (16).