Fish Health Booster. eSHa Optima is a unique combination of trace elements, minerals and vitamins that are missing from your tap water. These ingredients help recreate the natural enviornment your fish deserve. Your fish will flourish and you will see the results. Boosts fish health. Increases resistance against disease and parasites. Speeeds up recovery of sick and injured fish. Helps induce spawing. Treats 2000 litres (440 gallons).