Calcium & Total Hardness Test (compleximetric titration testing in general);
More is not always best! Especially n the use of indicators in compleximetric titrations , the indicator itself complexes with the determinant and this is then replaced by the stronger complexant e.g. E.D.T.A. However too much indicator produces a competitive situation between the two complexants that leads to drawn out end points. Hence the use of liquid or powder indicators allows the analyst to add only sufficient indicator to provide an observable end point as opposed to tablet reagents. another advantage of this is the reduced cost.