Method and composition for use in the cyclic process for the efficient generation of chlorine dioxide in dilute solutions

A method for determine the relative bromide concentration in an aqueous system of an aquatic facility using a cyclic process, the method comprising:

• the cyclic process comprising activating bromide ions with an oxidant to produce free bromine, the free bromine oxidizes chlorite ions to produce chlorine dioxide, and reducing at least some free bromine back to bromide ions,
• applying a composition comprising a bromide donor and a tracer;
• the composition is applied to the aqueous system to sustain a bromide ion concentration ranging from 2 ppm to 5000 ppm;
• monitoring the tracer to determine the relative concentration of bromide ion, and
• sustaining the bromide ion concentration to ensure the cyclic process and subsequent microbiological efficacy is achieved.