Does the turned-off parameters change in water quality model

The manual says: "Clicking the “Params” button brings up the list of parameters whose simulation (i.e. advection and dispersion) can be switched on or off. However, even if a parameter is not simulated, since it is still part of the kinetics, the IC concentration is used for all of the kinetic calculations."My question is whether the parameters are allowed to change in the simulation. Is it fixed at IC, or it would increase/decrease later?Thanks,Hengchen

If the parameter is not turned on then it is not simulated and the IC will remain constant throughout the simulation.