The use of nanomaterials has made it possible to run processes with less pollution than conventional methods. Among these nanoparticles, nanocarbon tubes (CNTs), which have antibacterial properties, can be mentioned. Also, among the important bacterial pathogens in the fish breeding industry, the two aeromonas hydrophilia bacteria are one of the causative agents of septicemia and hemorrhagic sepsis and Yersinia rockair are the causative agent of oral antibiotic antibiotic bacteria. The aim of this study was to investigate the effect of magnetized tubes nanocarbon (CNT@Fe3O4) on two Aeromonas hydrophila bacteria and Yersinia rockair. To conduct research, nanomaterials were prepared by hydrothermal method, and their antibacterial effect in vitro was determined on the bacteria studied. Nano-carbon nanotubes synthesized by spectroscopic and microscopic techniques including X-ray diffraction spectrum, shaking sample magnetometer and vegetative electron microscopy were investigated. Ultimately, the results of the MBC (Minimum Concentration Test) showed that the opacity of OD for the aeromonas hydrophila bacteria was 1.42 in the control group. However, in treatments of carbon nanotubes at concentrations of 8, 16, 32 and 64 mg, this value is equal to 0.17, 0.14, 0.08 and 0 respectively. The OD of turbidity created for Yersinia rockair bacteria in the control group was 0.94. However, in treatments of carbon nanotubes at concentrations of 8, 16, 32 and 64 mg, this value was equal to 0.245, 0.194, 0.11 and 0.09 respectively. The results of the minimum germination test for both bacteria showed the same results. Finally, after summarizing and comparing the results of the research with other studies, it can be concluded that the use of magnetic nanocarbon in the filtration system of aquatic reservoirs could have a potential impact on the reduction of barbatoic content.