A formulation of a pathogen inhibitor or probiotic as a slurry concentrate of a hydrated metal oxide for applications in agriculture, aquaculture, and as an anti antibiotic in which the bioactivity, when applied by dilution, is controlled by a precursor of Reactive Oxygen Species, and the release rate is controlled by the particle size. The invention may include a means whereby the precursor concentration may be controlled to meet the requirements of the ecosystem, from the maintenance of an aerobic system, to killing pathogenic, anaerobic microbes, or producing sterile ecosystems. In addition, the metal oxide may be selected to provide essential nutrients for growth of the agricultural or aquacultural products.