BACKGROUND Cyanobacterial blooms have raised significant public health concerns due to the ability of some strains to produce harmful compounds in the water. Electrolysis has shown great potential to eradicate cyanobacterial pollution. However, all proposed electrochemical systems employ some type of mixing (e.g. pump circulation), which might not be suitable for application in a large ecosystem. In this study instead, a floating and mobile electrochemical system was configured and tested to treat cyanobacteria without mixing. The electrodes and a portable rechargeable DC power supply were incorporated in a floating vessel which was then mobilized in the water. RESULTS Floating and mobilizing the vessel without mixing resulted in significant cyanobacterial inactivation depending on initial Cl- in the medium. Cells treated in a medium with 60 mg L-1 Cl- did not re-grow when they were harvested and then re-incubated in optimum growth conditions for 30 days, whereas those treated in similar to 0.25 mg L-1 Cl- took 22 days before they re-grew, which is twice the time needed for growth compared with an untreated control sample. CONCLUSION This novel system may thus offer a simple and feasible method to tackle cyanobacterial blooms in large-scale aquatic ecosystems without the need for installing mixing equipments. (c) 2018 Society of Chemical Industry