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 biotic in which the bioactivity when applied by dilution is controlled by a precursor of Reactive Oxygen Species and the release rate 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.
