A respirometer with controlled water quality and computerized data acquisition for experiments with swimming fish

This paper describes the design of a modified Brett-type respirometer for use with fish up to 2 kg at swimming speeds as high as 2.5 m·s(-1). Control of the respirometer, experimental monitoring and data acquisition are performed by computer. Water velocity, temperature, pH, dissolved oxygen and carbon dioxide can be controlled at predetermined levels to enable experiments to be conducted over several days with minimal deterioration in water quality.