The Dispenser Is the Invention: A Draw-Coupled Chlorine Doser for the Household Storage Vessel, with Its Residual Budget to the Cup

SIMULATED, NOT MEASURED. A passive lid-mounted dispenser design doses at filling and boosts at each draw: fill-only dosing falls below the 0.2 mg/L floor by 48 h (0.183 mg/L) while draw-coupled dosing holds 0.809 mg/L at 48 h inside the 0.2-1.0 mg/L band, at US$0.97 chemical cost per 1000 L. Design concept only; nothing was built or field-tested.