An implantable fluidic valve actuated by osmotic pressure gradient and methods of operating it are provided. The valve includes: an input fluid channel; an output fluid channel in fluid communication with the input fluid channel at an aperture; and a semi-permeable membrane forming a portion of a sealed chamber. The semi-permeable membrane may have an outer surface forming a wall of the input fluid channel, and an inner surface forming a wall of the sealed chamber, the membrane being configured to allow diffusion of a solvent into and out of the sealed chamber; and a first electrode and a second electrode disposed within the sealed chamber configured to receive a voltage. A pump including the above elements and a check valve is provided. An ocular implant including an inlet tube sized to receive aqueous humor and an intra-ocular pressure control system having a fluidic valve as above is also provided.