In proposed investigation, author offered numerical studies on gyrotactic micro-organisms in nanofluids by ohmic heating effect saturated in porous medium. Similarity transformations are taken into consideration to convert PDE into non-linear coupled ODE and thus solved by 5th-order Runge-Kutta-Fehlberg method by shooting technique. Physical parameters were explored on various profiles say velocity, temperature, concentration, and density of gyrotactic micro-organisms. Outcome of proposed investigation explores that with increasing effect of bioconvection Lewis number, bioconvection Peclet number and micro-organisms concentration difference parameter result in decline of density of motile micro-organisms’ profile. Code validations of proposed investigations were done with existing results in literature. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC part of Springer Nature.