Hi Yu Zhang,
We have set up a discussion here. We will try to help you then.
Currently the standard calibration allows you to fit parameters (with a same coefficient for all your model) with one objective function that you can build from your 24 stations for example.
So it depends of your goal and if your stations are in the same basin.
Did you find the calibration tutorial on the CWatM manual?
Thanks.
Luca