High-performance liquid chromatography was used to quantify residues of oxolinic acid and flumequine in muscle of wild fish caught in the vicinity of fish farms using the LiftUp feed collector system or a hydroacoustic feed detector during medication. Both systems are designed to minimise feed waste and thereby the amount of medicated feed entering the surroundings. The result indicates that both systems decrease the supply of medicated pellets to the wild fish during medication, since the mean and maximum concentrations of drugs in muscle of wild fish were reduced compared to fish farms not using this equipment. Therefore, the equipment will reduce the environmental impact of antibacterial agents used in fish farming.