Photosynthetic productivity has the potential to capture and store atmospheric carbon as biomass. Trace metal nutrient limitations often constrain the capacity for carbon capture and fixation in marine photosynthetic algae. Increases in algal CO2 uptake and carbon sequestration can be achieved by removing nutrient limitations to growth and metabolism via the local addition of nutrients. To address this, open ocean iron fertilization was tested at-scale in the 1970s, but the experiments were conducted with little control, generating public concern. However, as marine carbon dioxide removal (mCDR) is a topic of growing interest both within DOE (FECM, WPTO etc.) and private sector (Climate Works Foundation, Ocean Visions etc.), interest in open ocean Fe fertilization is resurging as an avenue to achieve scalable ocean decarbonization. The aim for the new generation of Fe-fertilization experiments is to have significant control on delivery so benefits are maximized, and any potential unintended ecosystem impacts are minimal. To that end, unlike the original experiments which relied on one-time addition of chemicals shipped to the open ocean, we have developed and demonstrate here an electrochemical method for controlled addition of Fe for maximum benefit and process control. Not only can electrodes containing Fe be placed local to algal populations and fertilization initiated without human intervention, but dosage can be kept to controllable minimums and in a bioavailable form. We demonstrated an 890% increase in harvest densities of algae cultures fertilized via electrochemical iron leaching compared to controls. This is the first example of electrochemically controlled nutrient fertilization in algae cultivation. Electrically iron-dosed cultures captured 1.04 ± 0.29 g L-1 day-1 CO2 during maximum growth, 10 times more than iron-limited cultures. We refer to this as 'precision electrofertilization". While we demonstrate the concept for Fe, the same method can be extended to various other micronutrients that are critical to the growth of algae (e.g., Mn, Zn, etc.) by simply changing the alloy of the electrode and electrochemical process conditions. Note that while this work originated from our interest in marine carbon dioxide removal in the open oceans, the near-term applications are likely to be in near-shore or on-shore aquaculture where controlled nutrient delivery can generate significant increase in productivity.